A rising trend in eco-friendly products: A health-conscious approach to green buying

Abstract

This study aims to develop and test the hypothesis of the relationship between green perceived value, green perceived risk, green trust, and green purchase intentions especially the moderator effect of gender on relationship of green trust and green intention to clarify their correlation. This study focuses on the interdependence between the four factors mentioned (green perceived value, green perceived risk, green trust, and green purchase intentions) in order to increase green purchase intentions in modern society, which is an important factor to be concerned about in this environmental era. The technique of research applied in this study is nonprobability sampling with snowball sampling method. Structural Equation Modeling (PLS-SEM) was used to test the cause and effect relationships in the research. A survey conducted by 214 respondents who concerned in buying eco-friendly product were asked to fill the questionnaire to analyze the hypothesis. The analyzed results show that the moderator effect of gender on relationship of green trust and green intention, green perceived value has a positive effect on both green trust and green purchase intentions. Then, green perceived risk positively affects green trust but has no impact on green purchase intentions. In comparison, green trust is an important factor that leads to green purchase intentions.

Highlights

• •This research investigates the impact that green marketing can have on consumers' intentions to make environmentally conscious purchases
• •Well-planned green marketing to improve the green purchase intention in order to offer businesses with information for establishing green strategies
• •Investigate the relationship between perceived green value, perceived green risk, and green trust in order to gain a better understanding of how to boost public interest in environmentally friendly products, particularly among citizens.

1. Introduction

In recent years, awareness of the environmental issue has been raised and popularized globally. Most countries in the world apply laws to protect the environment [1]. And develop a sustainable economy [2]. Besides the government's regulations, the increase in people's awareness of environmental issues and the demand for friendly environment products in recent years has led to the development of the ecological product industry [3]. For this reason, many organizations, from service firms to industrial companies, have been developing their green marketing strategies [4] in order to adapt to the needs of customers and to follow the trend.

In contract to the trend mentioned above, even though there are many stories in marketing literature about being green and caring for the environment, there are not that many empirical studies that demonstrate how businesses can combine and use green marketing in their daily operations. According to Geels et al. and Kotler, relying on eco-innovations, and environmental add-ons at the margins of marketing strategy has not resulted in transformative change for individuals and society, nor has it provided businesses with a substantial competitive advantage and value [5,6]. This study discusses the need for a more comprehensive and integrated study of green marketing practice. This is accomplished by developing a concept of green marketing orientation that defines the components of an organization that allow it to function as a green marketing-oriented one. This closely related to the consumer's green purchase behavior.

Recently, Vietnamese people's awareness of environmental issues has been increasing and popularizing due to the development of the Internet. Many environmental protection trends occurred in Vietnam and attracted lots of attention, especially from the young generation. One of the most famous trends in recent months that interest many Vietnamese citizens is the trend name “Challenge for change”, which means that the attendants will share two pictures of a place, one is before and one is after they collect the garbage there. Another typical example of the increase in Vietnamese people's awareness about the environment is that many people refuse to use plastic products in daily activities. Therefore, this study concentrates on the goals of well-prepared green marketing to enhance the green purchase intention to give some information for firms to develop their green strategies specially in the moderator effect of gender on relationship of green trust and green intention. According to Cheng and Chang, the green purchase intention correlates with three other factors, which are green perceived value, green perceived risk, and green trust [7]. This study aims to identify the respect between those factors to have a clearer understanding of how to increase the interest in using the friendly-environment product for society. This study seeks to explore the underlying connections among these factors to gain a deeper understanding of effective approaches for fostering societal engagement with environmentally friendly products. In light of this objective, the fundamental research question of this study centers on elucidating the impact of green perceived value, green perceived risk, and green trust on green purchase intention, with consideration for both direct and mediated effects.

This study has two novel aspects: (1) previous researches investigated the relationship between trust and risk and purchase intention in a variety of industries, whereas this study focuses on customer green behavior in green product/service consumption; and (2) this study measures the effect of gender as a moderator to determine whether or not it influences the relationship between green trust and green purchase intention. The emphasis on customer green behavior arises from the growing significance of environmental sustainability and conscious consumer choices. As environmental concerns and awareness increase, understanding how individuals engage with green products and services becomes crucial. By examining customer green behavior, the study aims to contribute to the understanding of factors that influence environmentally responsible consumer choices. This perspective adds value by providing insights into a specific context that previous research might not have adequately addressed.

While previous studies have explored the link between trust, risk, and purchase intention across various industries, this study's focus on green behavior in the context of green product and service consumption is relatively novel. This gap in the literature underscores the need to investigate how trust and risk perceptions affect individuals' intent to engage with eco-friendly products and services. By addressing this research gap, the study sheds light on a specialized area that holds particular importance in the current sustainability-driven landscape.

Incorporating a moderator, such as gender, is intended to provide a nuanced understanding of the relationship between green trust and green purchase intention. Moderators help to identify conditions under which the relationship between variables is stronger or weaker. In the context of gender as a moderator, the study aims to explore whether gender differences influence how trust impacts purchase intention regarding green products or services. This can lead to insights into potential variations in consumer behavior based on gender, allowing for more targeted and effective marketing strategies in the green marketplace.

The focus on customer green behavior addresses the contemporary importance of sustainable consumer choices, while the introduction of a moderator like gender aims to uncover potential variations in the relationship between trust and purchase intention. These aspects collectively contribute to a more comprehensive understanding of consumer behavior in the context of green product/service consumption and provide valuable insights into an underexplored area within the field of research. Thus, based on this change in consumer buying behaviors, following the trend and understanding the factors to enhance the green purchase intention of consumers are a great competitive advantage for firms, and it is also the purpose of this study. However, in order to apply an effective green marketing strategy, companies should apply it to all aspects of their operation [7]. Firms should pay attention to building up a green image in society's mind and caring about doing all the activities which are not harmful to the environment [8]. In addition, some studies show that customers are willing to pay a higher price for a friendly-environment product compared to a normal one which has the same function if that green product is valuable for the environment [9]. Thus, if firms can create and adapt an effective green marketing strategy, it is a great chance to build up a good image in the customer's mind and develop themselves.

2. Literature review

In this era, there is a change in the buying decision behaviors of the customers. They quickly realize the rapid deterioration of the environment and grow skeptical of company environmental policies. It forces companies to develop environmental programs and green products [10]. This change resulted from the increase in people's awareness of environmental issues and the demand for environment-friendly products [11]. It has been researched that consumers can accept a higher price for products that are not harmful to the environment [12]. More than 70% of Americans support environmental protection, in 49% declare that they are not going to use the product when such a product is harmful to the environment [13]. For that reason, green marketing has become a required strategy for firms to enhance competitive advantages [14].

However, the definition of green marketing is usually associated with products which are advertised to have eco-friendly characteristics, harmless to the environment or able to be recycled. Although those elements in the promotions are parts of green marketing, green marketing includes a wide range of factors besides green promotion [15]. According to Henion and Kinnear, the early concept of green marketing was defined as “the study of the positive and negative aspects of marketing activities on pollution, energy depletion, and non-energy resource depletion” [16]. This concept originated in the 1970s when “ecological marketing” was created due to environmental concerns [16]. Green marketing is also linked with the firm's strategy, which is planned to sustain and raise the awareness of the customers about environmental issues and their behaviors [17]. Thus, the firms can gain a more competitive advantage compared to competitors if they understand and develop factors that have strong impacts on the buying decision behavior of customers toward eco-friendly products [18]. During the 1990s, an investment of $200 was made by the firms in the United States to convert the product “green”. It was reported by The Marketing Intelligence Service that the share of “green” products of totally new products rose from 0.5 to 9.2% from 1985 to 1990 [19]. This study's purpose is to define the interdependence between green perceived value, green perceived risk, green trust, and their affection for green purchase intention.

2.1. Theoretical background

Theory of Planned Behavior (TPB) and (2) Theory of perceived risk (TPR) are the two theories used as the basis for this study [20,21].

The convergence of the Theory of Planned Behavior (TPB) and the Theory of Perceived Risk (TPR) in this study was realized through the integration of specific constructs that collectively provide a comprehensive understanding of individual behavioral intentions and perceptions in the context of green consumption, encompassing environmentally conscious choices. From the Theory of Planned Behavior (TPB), constructs such as Green Purchase Intentions and Green Perceived Value were thoughtfully chosen to capture the motivational and value-related aspects of individuals' green consumption decisions. These constructs aptly reflect the dynamic interplay between personal motivations and the perceived benefits of eco-conscious choices. Complementing these constructs, the Theory of Perceived Risk (TPR) contributed the construct Green Perceived Risk. This construct focuses on the potential negative consequences of green consumption choices, offering insight into the risk perceptions that may influence individuals' decision-making processes. The TPB constructs of Green Purchase Intentions and Green Perceived Value intertwine to illuminate the motivating factors behind individuals' intentions and actions toward green consumption. Green Purchase Intentions encapsulate their proactive commitment to engage in eco-friendly behaviors, while Green Perceived Value delves into their perception of the worth and advantages associated with such choices. Simultaneously, the incorporation of Green Perceived Risk from the Theory of Perceived Risk adds depth to the framework. This construct underscores individuals' concerns regarding potential drawbacks or negative outcomes of environmentally conscious decisions, providing a counterbalance to the positive motivations. Through the fusion of these constructs, the study gains a holistic understanding of how personal motivations, value perceptions, and risk considerations intersect to shape green consumption behavior. Green Purchase Intentions and Green Perceived Value, emanating from TPB, highlight the affirmative motivations and perceived advantages that drive individuals to opt for environmentally friendly alternatives. Meanwhile, Green Perceived Risk, rooted in TPR, brings attention to the potential risks that might impact these intentions. By connecting the dots between the constructs, the study reveals the intricate interplay between proactive motivations, value-based considerations, and risk perceptions. This integrated framework not only acknowledges the positive factors motivating green consumption but also recognizes the role of potential risks in influencing individuals' intentions and decisions. By merging constructs from both TPB and TPR, the study offers a comprehensive view of the multifaceted dynamics driving green consumption behavior, contributing to a deeper understanding of the complexities inherent in environmentally conscious choices.

2.2. Define the theory of the factors

2.2.1. Green perceived value

Green perceived value is defined as the benefits and the costs that customers can get/pay to the providers [22]. According to Chen and Chang, green perceived value is determined as “a consumer's overall appraisal of the net benefit of a product or service between what is received and what is given based on the consumer's environmental desires, sustainable expectations, and green needs” [23]. This means the customer's assessment of the value calculated between the product they bought and how it appeases their need to protect the environment. In another study, green perceived value is separated from two relative perspectives. The first aspect is about the economic perspective that the value is associated with the amount of money that customers pay for what they can get back, the price of the product. The second aspect is related to a psychological perspective which depends on the understanding of customers about products and factors that affect the buying decision [24]; each customer has their knowledge and requirements that must be met before deciding to purchase a product. Moreover, green perceived value can create an advantage in developing an effective promotion strategy [25]; by providing the exact value of the product matching the price tag, the product can be more attractive when meeting extra customers' green needs. In this study, green perceived value is defined as aspects of products that can satisfy the customer's needs and expectations. Thus, companies which can provide a valuable product which meet the demand of customers can attain a good image from customers' perspectives and lead to the development of the firm's economic status. For example, Tesla company produces its electronic model with high quality, truly committed to being friendly to the environment; in addition, its product's function and performance are also as good as qualified normal cars, which are the same segmentation. That is the extra value customers are looking for; instead of just getting the product, the customer will get the support with their cause of protecting the environment; and without the extra price, the customer gets more value than buying from other companies, therefore will be more inclined to get the product from Tesla. Thus, Tesla's products launched successfully and would still be developed in the future.

2.2.2. Green perceived risk

Perceived risk is categorized in two perspectives which are the consequences and uncertainty in products [26]. Studies show that perceived risk occurs in buying decisions when the buyers are uncertain about their choices and they're more valuable alternatives in the lists of products [27]. Knight distinguished between risk and uncertainty. Knight argued that whereas “risk” refers to anything with an unknown probability, “uncertainty” refers to a situation in which an exact probability is unknown [28]. Despite the fact that a difference has been made between uncertainty and risk with respect to the distribution of outcomes, marketers have consistently permitted the two concepts to be used interchangeably. This is because, as far as most marketers are concerned, customers are never aware of the true. This is when there are too many products for customers to choose and it leads to confusion in making the right purchase. While in the study green perceived risk is categorized into 7 elements which are “financial, performance, physical, psychological, social, time, and opportunity cost risk” [29]. In this study, green perceived risk is defined as the factors evaluated by consumers which possess the consequence, uncertainty, and create barriers to the buying decision making process. For instance, take the example of Tesla; if the price of Tesla's product is much higher than normal cars from other companies which are in the same segment, but the performance of Tesla's product is worse than theirs, it is a risk that customers may consider not purchasing an electronic car produced by Tesla. This means even with meeting customers' green needs but providing worse value with the same or higher price than other companies, Tesla's products will be refused by the customers due to the financial risk when purchasing.

2.2.3. Green trust

Trust is a concept which depends on the expectations of customers regarding the function, ability, and value of elements that belong to objectives that are in the evaluation [30]. While according to Chen & Chang, the idea of green trust is determined by "consumer's willingness to depend on a product or a service of a brand as a result of his belief in its environmental credibility, benevolence, and ability” [21]. This is how much the customer believes in the company's service to the environment. Other studies show that trust is the relationship between the disadvantages and the value which forms expectation of people of a subject, which is identified in the study by Rousseau as a psychological state comprising the intention to accept vulnerability based on positive expectations of the intentions or behavior of another” [31]. The concept of green trust in this study is defined as the element that drives the positive effect on the decision-making process in order to make brand choices and purchase products/services [32]. This can be translated to the customer's own belief in their financial risk to the positive outcome of helping the environment from the company products. It can be observed in the reality that after the first model of Tesla's electric car was introduced to the market and was able to attain the trust of consumers, then its next model, such as Tesla Model S and Tesla Model X was perceived positively by both experts and customer's evaluation. The credibility of experts and customers created a brand that is trusted to purchase by many other customers, which raises the value of the product even more.

2.2.4. Green purchase intentions

In the definition rooted in the study of Netemeyer and Morrison, green purchase intention is determined as “the likelihood that a consumer would buy a particular product resulting from his or her environmental needs' [33,34]. This is when green needs factors when a customer makes a buying decision, which varies from person to person. Green purchase intention is also studied as the tendency to decide to purchase friendly-environment products/services which have a positive impact on the environment [35]. In contrast, it is argued that purchase intentions are affected by the elements of customer awareness, behaviors, and perceptions [36]. It is studied that green purchase intention has a strong relationship with the awareness of environmental issues, which means people with a mindset of saving the environment are willing to buy more eco-friendly products compared to others who do not pay much attention to those kinds of problems [37]. How much information a customer has on environmental issues creates their evaluation of a product; the more the customer knows about how exactly a product helps the environment, the more requirements that products must meet to be chosen. In the context of this study, perceive green purchase intention is considered as the willingness to buy friendly-environment products/services due to the consciousness of enhancing the environment status. Green purchase intentions are the term on which many organizations in the world are concentrating due to the increase in the awareness of saving the environment. For example, Porsche and Mercedes Benz are developing their own model of electric cars to adapt to the increasing green purchase intentions of customers. The Internet has greatly expanded the customers' knowledge of the environmental issue, so companies need to keep up with meeting all their customer's green needs.

2.2.5. Hypothesis development

H1

There is a significant and positive relationship between green perceived value and green trust.

Green perceived value, as mentioned, is the value of products/services' aspects such as price, the effect on the environment, and function that are studied to have a positive influence on the trust of consumers because the value provided by the products/services is able to satisfy the expectations and demands of users [7]. When customer green needs are met, the value is approved by the customers, and it creates trust in the service and the products. The interdependence of green perceived value and green trust in the study of Chen, Lin, & Weng showed that the trust between customers and providers could be improved through the quality and value of products/services which are perceived/provided [38]. Customers will give trust credibility when the product they provide matches its value with the price they pay, and making sure this value is a guarantee is important to create trust. Tesla provides an electronic car model with high quality, a matching price, and is friendly to the environment; this value is reviewed and creates trust in the product for other customers, which generates even more credibility. Thus, this study applied the hypothesis to research that green perceived value positively green trust.

H2

There is a significant and positive relationship between green perceived risk and green trust

There is a significant and positive relationship between green perceived value and green purchase intentions.

Studies showed that the decreasing of green perceived risk leads to the enhancement of customers' intention to purchase products/services, which means that green perceived risk is considered a factor that negatively influences green trust [39]. The credibility of your product is affected by the duration and how stable the products are when consumed by the customers. The result of the study also defined that green perceived risk has a negative impact on green trust due to the uncertainty and the consequences of products/services which are evaluated by users [40,41]. The product value, when not guaranteed, can lower the trust of the user. When the customer uses an unstable product, they will create bad reviews and reputation of the product; then other customers choosing a list of products, they won't decide on the product that has a low reputation since it is risky to purchase when such a product is labelled unstable. When Tesla cars are not provided consistent results, clients will not believe in the product's ability to provide value to use and help the environment. In this study, green perceived risk is mentioned as the factors included in products/services which negatively affect green trust.

H3

There is a significant and positive relationship between green trust and green purchase intentions

Previous research showed that there is a meaningful interdependence between green trust and green purchase intentions. The high credibility of products and brands in customers' perception drives the high tendency to decide on brand choices and purchasing products/services [42]. The customer tends to purchase the product with credibility provided by other buyers or experts. The factors such as quality, function, and value to the environment are considered to have a good impact on green trust if those factors are truly qualified as advertised and meet the expectation of customers. This is also a competitive advantage for brands which has suitable strategies to build up their reputation and credibility compared to other competitors in the industry because customers are studied to make choices based on their trust in brands to purchase products which have less damage to the environment [42]. A company learns the customer requirement for a product to be friendly to the environment by accessing online sources of knowledge which is the arising environmental issue; then improve their product to solve these problems and meet as many customers' needs as possible. The study of electric cars can be appealing to many people since electricity is a resource they got access to and proven by scientists that they do not create any pollution to the environment. Thus, this study applied the hypothesis that green trust has a positive impact on green purchase intentions.

H4

There is a significant and positive relationship between green perceived value and green purchase intentions

The value of a product, such as quality and price, is studied to create a strong impact on buying decision making of customers compared to alternatives [43]. The reason for this relationship is rooted in the resources used to evaluate products/services by customers, and it is usually based on the value that products/services can bring to them. It is studied that if brands are able to build up the product with valuable attributes, it is meant to enhance the purchase intentions due to the promotion by users through feedback and word of mouth [25,44]. It is important to develop valuable products to enhance purchase intentions in this environmental era. When choosing from a list of products, customers often choose the product which offers the best value to purchase. A car value has to provide the same or better value; otherwise, the product can be switched to other companies. Thus this study determines that green perceived value affects positively green purchase intentions.

H5

There is a significant and positive relationship between green perceived risk and green purchase intentions

In this era, there are thousands of products that possess the same function as each other, so it leads to the hesitance in the customer's attitude to decide which brands should be chosen. The reason for this issue comes from the uncertainty of products considered the risk in the customer's mind. According to Kim et al. [45] green perceived risk creates a barrier to the decision-making process of customers to decide if they should buy particular products/services. When making the intention to buy a product, an unstable or questionable, bad rated product can make customers hesitate and look for more guaranteed products somewhere else. It can be explained that if customers think that a product or service does not have clear information or not a well-known, unqualified function, they tend to not choose that product/service because it is considered a risk. For example, if an electronic car is advertised as friendly to the environment, but in reality, that car consumes some electronics which is calculated to be more harmful to the environment than normal cars, customers will refuse to purchase that car. Thus, in this study, green perceived risk has a negative impact on green purchase intentions.

Based on the hypotheses mentioned above, the research model is established (Fig. 1).

Fig. 1.

Research model.

3. Methodology

3.1. Research design and data

Two distinct phases—the pilot research phase and the formal research phase—comprised the execution of this investigation. The pilot study utilized two methods: the first method was an in-depth interview technique, which checked the validity of the scale in comparison to the research context in Vietnam; the second method was a pilot study that involved 100 respondents. After that, the phase of conducting the formal research is finished. In this study, the research hypotheses were put to the test through the application of causal analysis.

Google Form is an instrument for creating inquiries. The research paradigm is founded on 23 queries. The questionnaires were distributed primarily through the Internet, postal mail, Facebook, and Zalo. When questionnaires were sent out, the objective of the survey was made abundantly obvious, and respondents were committed to responding thoughtfully. There were 214 residents of Vietnam who participated in the survey, to establish an appropriate sample size for their empirical research, the researcher considered the robust inverse square root method proposed by Kock and Hadaya [46]. By assuming a significance level of 5% (α = 0.05) and a minimum path coefficient of 0.2 based on their theoretical expectations, they applied the following formula Nmin > (2.486/0.2)2 = 154.505.

To ensure practicality and meaningful results, the calculated minimum sample size was rounded to the nearest integer, resulting in 155 participants. The researcher recognized the importance of striking a balance between statistical rigor and practical feasibility. While the formula indicated a minimum of 155 respondents, the researcher considered factors such as potential attrition, data variability, and the research's complexity. Thus, the researcher chose a slightly larger sample size of 214 respondents. This decision accounts for potential challenges that could affect the sample during the research process while ensuring that the results remain reliable and robust. The selected sample size aligns with the method's conservative approach and serves as a strategic compromise between statistical validity and practical constraints, enhancing the study's overall quality and findings. Non-probability sampling was employed in the study. The research technique utilized in this study is nonprobability sampling utilizing the snowball sampling technique. This study utilized snowball sampling because it is challenging for researchers to obtain the desired number of respondents due to the small size and geographical dispersion of the population under study. The survey was sent to a limited group of respondents for the purpose of research. The respondent will share the questionnaire with their peers after concluding the survey. Our strategy is the avalanche sample. In addition, all respondents are aware of the purpose of the study, and there is no deception involved. This study pertains to direct communication.

The SEM model is used to conclude the hypotheses of the research model. The PLS-SEM model is an extension of the general linear model that permits researchers to investigate multiple regression equations in order to determine complex model relationships. The model fix was assessed, factor analysis, and network diagram correlation analysis. Bootstrap iteratively evaluates model dependability. This method replaces expensive double-sampling. The crowd is the original Bootstrap template. In this investigation, 500 bootstrap samples are used. Estimated mean and bias from multiple samples (bias). When bias is minimal, it is possible to rely on model estimates. The researcher passed the data through Smart-PLS software after filtering, validating, coding, and inputting it. Effective value is the most important aspect of an applicable scale that corresponds to the research concept for a research model depicting the relationships between latent variables.

3.2. The measurement of the construct

To measure the response level of the respondents, for each question, the scale was used from 1 “strongly disagree” to 5 “strongly agree”. The questionnaire is divided into two parts; the first part is the demographic questions is provided to classify the subjects of gender, age, and income. The second part includes 18 questions to assess their awareness and attitudes towards green products. The measurements of the structures in this study are the following.

• (1)Green perceived value. In terms of Patterson and Spreng [47], this study propounds the green perceived value concept and defines it as the overall evaluation of the consumers about the net benefit of the product or service. This evaluation is dependent on the environmental desires, sustainable expectations, and green needs of the consumers. In addition, the green perceived value is measured by five items [7].
• (2)Green perceived risk. This paper proposes the concept of “green perceived risk” in terms of Peter and Ryan to define it as the expectation of the negative environmental results that are coherent with purchase behavior [48]. This study also refers to Jacoby and Kaplan and Sweeney et al. to measure green perceived risk, and its measurement includes five items (3) Green trust [25,29]. According to Chen [49], this study defines “green trust” as “a willingness to depend on a product, service, or brand based on the belief or expectation resulting from its credibility, benevolence, and ability about its environmental performance”. Besides, this paper refers to Chen [49] to measure green trust, and its measurement includes four items (4) Green purchase intentions. This study proposes a novel notion, “green purchase intentions”, and refers to Netemeyer et al. and Morrison to define it as the possibility that “a consumer would purchase a particular product led from his or her environmental needs” [33,34]. Besides, this paper refers to Pavlou and Chang and Chen to measure green purchase intentions, and the measurement includes three items [39,50].

4. Results analysis

The result showed demographic figures included 214 respondents participated in the survey, mainly living in Vietnam. 50,4% are male, 47,2% are female, and the rest is LGBT. In terms of age, 50% are from 15 to 22 years old, 41% are from 23 to 35 years old, and the rest are more than 35 years old (9%). The main occupation is students, accounting for 56.9%. 20.3% of respondents do business, 20% are official and other jobs. The average income is mostly less than 10 million VND per month (53,2%), 29,8% from 10 to 20 million VND per month. More than 90% of the respondents used to use eco-friendly products, and they were concerned about environmental issues through sources such as school (12%), celebrities (16,9%), friends or relatives (16,9%), and many of them are aware of this issues by themselves (more than 50%). Through demographic answers, it can be realized that the majority of respondents are quite young, mostly from 15 to 35 years old, with an average income of 5–20 million a month. But most of them are already using and being environmentally conscious and green products. Cronbach's Alpha is a test to analyze and evaluate the reliability of the scale. The total variable correlation coefficient is the level variable that “links” between one observed variable in the factor and the other. It reflects the contribution to the conceptual value of the factor of a particular observed variable. The criteria for assessing whether a variable contributes value to the factor or not is that the minimum requirement of Cronbach's Alpha should be greater than 0,7. The higher the Cronbach's Alpha index is, the more reliable the variable.

Outer loading and measurement scales were adapted and adjusted from Chen and Chang [7]. Based on this table, Cronbach's alpha coefficient of “Green perceived value” is 0.739, “Green perceived risk” is 0.759, “Green trust” is 0.803, and “Green purchase intentions” is 0.808. All constructs >0.7, so the results are acceptable in reality (Table 1).

Table 1.

Outer loading and measurement scales.

Green Purchase intention	Outer Loading
I purchase this product because of its environmental concern	0.887
I purchase this product in the future because of its environmental performance	0.859
I purchase this product because it is environmental friendly	0.801
Green risk
There is a chance that you would get environmental penalty or loss if you use this product	0.922
Using this product would damage your green reputation or image	0.870
Green Perceived value
Product has more environmental concern than other products	0.831
Product is environmental friendly.	0.811
Product has more environmental benefit than other products.	0.789
Green Trust
Overall, you are glad to purchase this product because it is environmental friendly	0.834
You feel that this product's environmental claims are generally trustworthy	0.843
This product's environmental concern meets your expectations	0.865

The result of this study shows that the KMO coefficient figure is 0.742, which is greater than 0.5 and less than 1 (0.5 < KMO <1). It means that the factors included in this study are evaluated as qualified and suitable for the factor analysis process. In addition, the Sig value is less than 0.05, which means that factors are interdependent. Moreover, the total variance explained value is 72.845% > 50% which means that it is qualified, and the extracted factors are able to describe 72% of the total elements.

Using Cronbach's alpha and the Dijkstra-rho Henseler index (rho A), the scale reliability for each collection of model components was evaluated. The Cronbach alpha coefficient is used to determine the change in each variable as well as the correlation between variables. If Cronbach's alpha is greater than 0.70, it indicates reliability [51]. The subsequent CFA analysis verifies if the observed variables for each factor are consistent with the model. Without bias from measurement error, CFA can test the theoretical structure of measurement scales, such as the relationship between research topics. (1) The scale of uni-dimensionality is appropriate for market data when it meets the following criteria: Chi-squared index 2/df with p 0.05, CMIN/DF (Chi-squared adjusted for degrees of freedom) less than 2 to 5, GFI (Goodness-Of-Fit Index) 0.90, CFI (Comparative Fit Index) 0.90, TLI (Tucker-Lewis Index) 0.90, and RMSEA [52] Hair et al., 2010). (2) For Convergent Validity (CV), all normalized regression coefficients must be statistically significant and greater than 0.5. (3) The definition of reliability is CR (Composite Reliability) greater than 0.6, 0.6–0.7: Acceptable, and 0.7: Good [52,53]. Less than 0.85 for discriminant validity (DV) [54]. After focusing on and developing scales for the latent variables of the research model, we invited three university academics who teach entrepreneurship courses to validate the content of the measurement scales to ensure that all scales were translated correctly and were adequately clear. We sent the questionnaire to 50 respondents and measured the Dijkstra-rho Henseler index (rho A) to determine the questionnaire's reliability. Before conducting an empirical study, the validity and reliability of the scale must be validated to ensure that the model variables are acceptable. The internal consistency of each study concept is evaluated using factor analysis and reliability to demonstrate the discriminant and convergent validity of the Likert scale. Discriminant validity is determined by examining the correlation matrix between independent and dependent variables and selecting those with low correlation coefficients. Discriminant value defines the degree to which a scale (observed variable) is distinct from other variables that ought to be distinct. A high absolute correlation coefficient (0.85), indicating multi-collinearity, suggests that study topics may coincide and measure the same concept (Table 2). To satisfy discriminant value requirements, the topic's research concepts must have a correlation coefficient below 0.85. Eliminate exploratory elements that do not align with theory and practice and collect those that do from qualitative research after evaluating them.

Table 2.

Validity and reliability.

Discriminant Validity	Green Perceived value	Green Purchase Intention	Green Trust	Green Perceived Risk
Fornell-Larcker Criterion
Green Perceived Value	0.695
Green Purchase Intention	0.694	0.770
Green Trust	0.763	0.796	0.759
Green Risk	0.109	0.297	0.289	0.794
HTMT
Green Purchase Intention	0.696
Green Trust	0.757	0.798
Green Risk	0.137	0.284	0.296
Convergent Validity	Cronbach's Alpha	rho_A	Composite Reliability	Average Variance Extracted (AVE)
Green Perceived Value	0.739	0.739	0.736	0.500
Green Purchase Intention	0.808	0.826	0.812	0.593
Green Trust	0.803	0.803	0.803	0.577
Green Risk	0.759	0.790	0.770	0.630

The path shown by the t-statistic is more than 1.96 or p-value <5% (0.05) (except H5), then hypotheses can be stated as supported. The result in Table 3 shows that all P values are less than 0.05 and 0.1, which proves that there are relationships between the hypotheses of the model significantly at significant levels 95% and 90% (H1, H2, H3, H4, H6) (Table 3).

Table 3.

Paths results.

Hypotheses expected sign	Paths	Coefficient	T Value	P Values
H1 +	Green Perceived Value → Green Trust (D and T)	0.573	10.380	0.000	Supported
H2 +	Green Perceived Risk → Green Trust (D and T)	−0.183	2.157	0.031	Supported
H3 +	Green Trust → Green Purchase Intention (D and T)	0.457	5.212	0.000	Supported
H4 +	Green Perceived Value → Green Purchase Intention (D)	0.230	2.905	0.004	Supported
	Green Perceived Value →Green Purchase Intention (I)	0.262	4.223	0.000	Supported
	Green Perceived Value →Green Purchase Intention (T)	0.492	7.808	0.000	Supported
H5 +	Green Risk coefficient → Green Purchase Intention (D)	0.097	1.375	0.170	Unsupported
	Green Perceived Risk → Green Purchase Intention (I)	0.084	1.878	0.061	Supported
	Green Perceived Risk → Green Purchase Intention (T)	0.181	2.228	0.026	Supported
H6 -	Gender x Green Trust x Green Purchase Intention →Green Purchase Intention (M)	−0.211	3.420	0.001	Supported

D: Direct effect; I: Indirect effect, T: total effect, M: Moderation effect.

The relationship between green perceived value and green trust from H1 is supported. This result is also in line with the research of Chen and Chang [23], which indicated the higher level of green perceived value, the higher level of trust that consumers put on the products/services. The relationship between the two constructs could be understood if a customer purchases a product because it has more environmental concerns, is environmental friendly and has more environmental benefits than other products, the customer will tend to trust and decide to purchase it consciously.

H2 hypothesis result also supported. This empirical test for this hypothesis is in line with the research of Chang & Chen [39], indicating that the decreasing of green perceived risk leads to the enhancement of customers' intention to purchase products/services, which means that green perceived risk is considered as factors that negatively influence green trust. It proved when the customer uses the uneco-friendly product; they will create bad reviews and reputation of the product; then other customers choosing a list of products, they won't decide on the product that has a low reputation since it is a risky purchase when such product is labelled unstable. Moreover, when customers think that there is a chance that they would get an environmental penalty or loss if they use this product or using this product would damage their green reputation or image, they will not trust that product anymore. The more risk customer perceives from the product, which damage the environment, the less trust customer will put on that product.

H3 was also supported after an empirical test. The research of [42] has equivalent results. The result implies that more trust in the eco-friendly characteristics of a product will lead to direct customer buying decision making. The customer tends to purchase the product with credibility provided by other buyers or experts. The factors such as quality, function, and value to the environment are considered to have a good impact on green trust if those factors are truly qualified as advertised and meet the expectation of customers.

H4 represented for green perceived high value will lead to more green purchase intentions. This expressed the close and positive relationship between these two constructs. It could be understood that when a customer perceives a product which has more environmental concerns than other products, is more environmental friendly and has environmental benefits than other products, they will put more effort into buying that product to consume. This is also in line with the empirical test result from Chen and Chang [23].

The influence of gender on the link between green perceived value and green purchasing intention is shown by Hypothesis 6 (H6) in the diagram. In the analysis of the data, females are represented by the code 0, and males by the number 1. The findings suggest that gender has a negative influence on the connection between green perceived value and green purchasing intention. Specifically, the results showed that this impact is negative if the gender variable rises from 0 to 1 (a shift from female to male among the respondents). This indicated that the connection described in H6 would diminish. It seems to imply that females have a more significant influence than men do on the association between green perceived value and green purchasing intention. It makes perfect sense since, in Vietnam, women care more than men about their appearance, their health, and the state of the environment.

5. Discussion

This study focuses on the role of green marketing in the purpose of enhancing green purchase intentions. In detail, we identify the relationship between the four elements belonging to green marketing, which are green perceived value, green perceived risk, green trust, and green purchase intentions. The relationship between green perceived value and green trust that Cheng and Chang [7] suggested that the greater the degree of green perceived value, the greater the quantity of trust consumers place in the products and services. If a client purchases a product because it is environmentally benign, has a greater number of environmental advantages than other products, and has more environmental concerns than other products, the client is more likely to have faith in the product and acquire it knowingly. When consumers have confidence in environmentally friendly products, they are more likely to intend to use them [55]. Quality, functionality, and environmental value are crucial trust-building factors for customers who intend to purchase environmentally beneficial products. Consequently, a growing number of women choose eco-friendly lifestyles, healthful diets, and the use of green products. The result also demonstrates that gender influences the relationship between green perceived value and green purchasing intention. Males are represented by the code 0 and females by the number 1 in the data analysis. The results indicate that gender has a negative effect on the relationship between perceived green value and green purchasing intent. In particular, the results demonstrated that this effect is negative if the gender variable increases from 0 to 1 (a transition from female to male respondents). This suggested that the connection described in Hypothesis 6 would weaken. It appears that women have a greater impact than men on the relationship between green perceived value and green purchasing intention. It makes perfect sense when you consider that women in Vietnam care more about their appearance, health, and the condition of the environment than males do. Modern Vietnamese women choose eco-friendly lifestyles, greener dining options, and greener product usage in increasing numbers [56]. The hypothesis is applied in this study is that green perceived value affect positively green trust, and green perceived risk has a negative impact on green trust which means that if the increase in the value of products/services leads to the enhancement in the trust of customers, in contrast, the trust of users decreases when they perceive a high risk of products/services. In addition, it also determined that green trust and green perceived value play an important role in enhancing green purchase intention. In comparison, green perceived risk is a factor that decreases the intentions to purchase products/services of customers. The hypothesis was developed to highlight the idea that understanding the relationship between the four factors, which are green perceived value, green perceived risk, green trust, and green purchase intentions, is helpful for firms to develop green marketing strategies as well as enhance their competitive advantage.

6. Managerial implication

In this environmental era, when environmentalism is more popularized day by day, people pay more attention to the ecosystem due to the negative changes of nature; companies must have suitable steps for adapting to the changes in consumer behavior. Thus, developing competitive green marketing is one of the best ways to solve this issue. This study suggests that if firms concentrate on improving green value delivered to customers can influence both green trust and green purchase intentions of customers positively. Hence, if companies can improve the quality of products, the environmental value, competitive price, and ensure that the eco-friendly products are able to perform as good as normal products which have the same function, it is meaningful for firms to gain the trust of consumers. In addition, reducing the absence of green perceived risk is also a way to enhance customers' trust. However, the data result showed that green perceived risk has a positive impact on both green trust and green purchase intentions despite the consequences and uncertainty of products/services. This situation can be explained that the risk included in products is overwhelmed by the value of the product and the reputation of the brand, or the trust of customers towards brands. In addition, it can be can clarified the illogical of perceived value's positive effect on trust and purchase intentions in the case of an energy drink which is studied to cause the consequences for human health, but the energy drink industry still has been developed because people perceive that the risk of health is overwhelmed by the value that they can get by consuming energy drinks (have the energy to work, keep awake, increase the alertness). In addition, increasing green perceived value and reducing green perceived risk is important to enhance green purchase intentions of customers besides their effects on green trust, especially if the companies are not famous and have not attained good images in the industry. This study determined that green purchase intentions have significantly relied on green perceived value. If companies are able to improve the quality of various aspects of their products from design, service, function, and green value, it is easy to understand that customers will have more tendency to purchase those kinds of products. Hence, if companies focus on eliminating the uncertainty and consequences of their products, it gives the consumers more reasons to buy. Finally, it is important to understand that green trust plays an important role in the relationship between the four factors. It can be observed that the role of green trust can be considered as a bridge to connect other factors. If companies can enhance green trust in customers' perception, it means green perceived value and green purchase intention are also increased; in contrast, the green perceived risk is lowered based on the enhancement of green trust.

7. Conclusion and future research

The research solved the research question how green perceived value, green perceived risk, and green trust influence green purchase intention indirectly and indirectly. The result confirmed that green perceived risk is a factor that has been shown to have a negative impact on customers' intentions to purchase products or services. The hypotheses were developed to highlight the idea that understanding the relationship between the four factors, which are green perceived value, green perceived risk, green trust, and green purchase intentions, is helpful for firms to develop green marketing strategies as well as enhance their competitive advantage. These factors are listed in the following order: green perceived value, green perceived risk, green trust, and green purchase intentions. The findings also show that gender influences the relationship between green perceived value and green purchasing intention, with a negative effect on the relationship between perceived green value and green purchasing intent. Women appear to have a greater influence on the relationship between green perceived value and green purchasing intention than men.

In this research, there are some limitations that we separated into three points. The first limitation is the scale of this research. This study just distributed the survey to research respondents who are not able to represent most of the population. Further research can broaden the scale of research. The second limitation is the hypothesis that applied four factors in order to enhance green purchase intentions. Further research can apply more elements to clarify the method to enhance green purchase intentions. The third limitation is the application that we do not clarify in detail what activities are attributed to which factors. Further research can concentrate on the activities that can help firms to increase green perceived value, reduce green perceived risk, gain green trust, and enhance green purchase intentions.

Ethical approval and informed consent

The author declares no competing interests.

Ethical approval

The author sought and got ethical approval from her institution's Research Ethical Board and the study complied with ethical standards. There was no number attached to the approval.

Informed consent

The researcher sought and got the consent of the participants to participate in the study. Out of the 214 sampled participants, 214 of them accepted and voluntarily participated in the study after the researcher assured them of anonymity and that their responses were solely for academic purposes.

Author contribution statement

Linh Nguyen: Conceived and designed the empirical research; Performed the survey.; Analyzed and interpreted the data; Contributed reagents, materials, analysis tools or data; Wrote the paper.

Data availability statement

The authors do not have permission to share data.

Declaration of competing interest

The authors declare the following financial interests/personal relationships which may not be considered as potential competing interests: Nguyen Tran Cam Linh reports The Ho Chi Minh City Open University does not provide sponsorship for this paper. However, after the journal's acceptance, the University will grant an award to the author at a later date.

Appendix A. Supplementary data

The following is the supplementary data to this article: