An integrated polyacrylonitrile fiber mat sensor for simultaneous temperature and pressure monitoring in high-temperature environments

Abstract

Flexible sensors capable of simultaneous temperature and pressure monitoring are highly desirable for electronic skin, wearable devices, and safety monitoring in high-temperature environments. However, existing flexible sensors are often limited by narrow operating temperature ranges, thermally induced signal interference, and insufficient durability under cyclic mechanical loading. This study develops a flexible wide-temperature-range temperature-pressure sensor based on polyacrylonitrile fiber mats. By combining laser processing or heat treatment, the electrical properties of polyacrylonitrile are regulated in situ, enabling its use as a multimodal sensing material. Temperature sensing is achieved through the thermosensitive effect of the treated polyacrylonitrile fiber mat, with a resolution of 0.1 °C in the temperature range of 25 °C–300 °C. Pressure sensing is realized through the piezoresistive response of polyacrylonitrile nanowires, featuring a measurement range of 0–480 kPa and response/recovery time of 53.2 ms/8.8 ms. After 10,000 loading–unloading cycles, the pressure-response attenuation remains below 1%, demonstrating good mechanical durability. Furthermore, the sensor exhibits reliable responses under dynamic thermal–mechanical coupling conditions and can be integrated with robotic grippers for simultaneous temperature and pressure perception. These results suggest that the proposed sensor holds promise for lithium-ion battery thermal management, industrial equipment condition monitoring, and emergency rescue applications in high-temperature environments.

Introduction

The rapid development of flexible electronic skin and smart wearable devices has created an urgent demand for sensors capable of simultaneous temperature-pressure monitoring across ambient to medium-high temperature ranges^1–5. In fire-related and other high-temperature scenarios, real-time monitoring of both temperature and pressure is essential for early fire detection, thermal runaway prevention, and personnel safety. However, traditional rigid sensors are generally unsuitable for such applications because of their limited conformability to curved, deformable, and dynamic surfaces^6–8. Although flexible sensors provide a promising alternative, existing devices still face several critical limitations^9–11. First, the operating temperature range is often restricted by the thermal instability of conductive sensing materials. Second, in dynamic thermo-mechanically coupled environments, thermal and mechanical stimuli may induce significant signal crosstalk, resulting in inaccurate characterization of contact states and thermal events. Third, cyclic mechanical loading can lead to performance degradation, thereby compromising long-term reliability. Overcoming these limitations is therefore essential for developing robust flexible sensors that can reliably operate in fire-prone and high-temperature environments, with potential benefits for early fire warning, thermal runaway prevention in energy storage systems, and safety protection in industrial and residential settings^1–3.

As shown in Fig. 1, by equipping search-and-rescue robots with these sensors, their robotic arms’ sensory capabilities will be enhanced. This will enable more accurate perception of fire environments and more precise control of the robotic arms, thereby preventing secondary damage to trapped individuals and valuable property^12–15. Therefore, material and structural innovations for flexible sensors are highly desirable to achieve reliable wide-temperature-range temperature–pressure monitoring in extreme environments.

Fig. 1.

In high-temperature environments, flexible sensors assist search-and-rescue robots in performing real-time temperature and pressure monitoring and providing feedback

In recent years, considerable progress has been made in flexible pressure sensors. In terms of sensitive materials, conductive hydrogels, MXene, graphene, and ionic conductors have been widely investigated. The ceramic matrix composite-based conductive hydrogel prepared by Dang et al. exhibits dual responsiveness to temperature and pressure, as well as self-healing properties and high extensibility¹⁶; Zhang et al. achieved simultaneous detection of pressure from 0 to 370 kPa and temperature from 23 to 58 °C using a graphene/MXene/cellulose composite system¹⁷. Furthermore, ionic composite nanofiber membranes and ionic gels significantly increase sensitivity, reaching up to 57.2 kPa⁻¹, through the electric double-layer effect^18,19, while the porous MXene structures combine high sensitivity with stability²⁰. Regarding substrates and structural design, PDMS, Ecoflex, and fabric substrates are widely adopted due to their excellent flexibility^21,22. By constructing gradient structures, wrinkled structures, and multi-level pyramid structures, the contact interface and stress distribution can be effectively regulated, enabling high sensitivity and a broad measurement range^23–25. For example, multi-level pyramid structures can achieve a sensitivity of up to 8775 kPa⁻¹²⁵, while gradient structures can realize a linear response range in the hundreds of kPa²³. In terms of fabrication processes, electrospinning, 3D printing, template transfer, and laser processing have been continuously developed^18,23,26, aiding in the construction of multi-level micro-structures. Despite these advances, most existing flexible pressure sensors are mainly designed for room-temperature operation because of limitations in material composition and thermal stability^18–30. In particular, the temperature dependence of pressure-sensitive materials can significantly reduce measurement accuracy under thermal loading, limiting their application in medium- and high-temperature environments. Therefore, a flexible sensing material that can maintain stable electrical and mechanical responses under thermal–mechanical coupling is needed for simultaneous temperature and pressure monitoring over a wide temperature range.

In this study, a flexible polyacrylonitrile-based temperature–pressure sensor was developed through laser in-situ processing or thermal treatment. By regulating the electrical properties of polyacrylonitrile fiber mats, the treated material can serve as a multimodal sensing material for both temperature and pressure detection. Temperature sensing is achieved through the thermoresistive effect of the treated polyacrylonitrile fiber mat, while pressure sensing is realized through the piezoresistive response of the nanofibrous structure. The assembled sensor enables reliable dual-mode monitoring over a temperature range of 25–300 °C and a pressure range of 0–480 kPa, with a temperature resolution of 0.1 °C and response/recovery times of 53.2/8.8 ms for pressure sensing. In addition, the sensor can be mounted onto a mechanical gripper to acquire temperature and pressure information of grasped objects in high-temperature environments. The flexible sensor provides real-time, reliable multi-parameter sensing capabilities for extreme scenarios such as fire rescue operations, safety monitoring of industrial high-temperature equipment, and thermal runaway protection for new energy batteries, thereby offering a promising approach for safety assessment and risk prevention in high-temperature environments.

Fabrication

Polyacrylonitrile fiber mats were used as the functional material for wide-temperature-range multimodal sensing. During fiber preparation, acrylonitrile was used as the main monomer, while small amounts of copolymer monomers such as methyl acrylate and methyl methacrylate were added to improve the spinnability of the spinning solution. Dimethyl sulphoxide and dimethylacetamide were used as solvents. The spinning solution was filtered to remove impurities and underwent degassing before fiber formation. During spinning, the solution was first extruded through a 5–20 mm air layer before entering a solidification layer of dimethylacetamide. The polyacrylonitrile fibers were subsequently washed with water and stretched in environments such as hot water or steam to enhance fiber density and strength, followed by drying at 150 °C. In the carbonization process of polyacrylonitrile fibers, the fibers were thermally treated in air at 200–300 °C for 60–120 minutes. During this process, chemical reactions such as cyclisation, dehydrogenation, oxidation, and cross-linking occurred, resulting in the fibers exhibiting electrical insulation properties. As shown in Fig. 2a, the polyacrylonitrile fiber mat was black in color and exhibited insulating characteristics. To regulate the electrical properties of the polyacrylonitrile fiber mats, laser in-situ processing or high-temperature furnace treatment was employed. After treatment, the polyacrylonitrile fiber mats exhibited conductive behavior and could be used as sensing materials. As summarized in Table S1, when the treatment temperature was below 600 °C, the polyacrylonitrile fiber mats remained electrically insulating. With increasing treatment temperature, the material’s resistivity decreases significantly. However, once the temperature exceeded 1100 °C, the polyacrylonitrile fiber mats again became insulating. Consequently, treatment temperatures at 600 °C ~ 1000 °C were selected for the control group. The treated polyacrylonitrile fiber mats were cut into the required shapes for subsequent sensor assembly. The assembly process of the flexible temperature–pressure sensor is shown in Fig. 2b. Polyimide was selected as the flexible substrate because of its good thermal resistance and flexibility. The Polyimide substrate was first cleaned and cut to the designed size. Gold/silver/copper electrode layers were fabricated using conventional micro-electro-mechanical system (MEMS) processes, including photolithography, exposure, and magnetron sputtering. In particular, interdigitated electrodes were designed to measure resistance changes in the polyacrylonitrile fiber mat s during temperature and pressure sensing. To ensure reliable bonding between the polyacrylonitrile and the flexible substrate, a screen-printing pattern complementary to the interdigitated electrodes was designed. High-temperature ceramic adhesive was then deposited by screen printing, enabling stable attachment of the polyacrylonitrile fiber mats under high-temperature operating conditions.

Fig. 2.

Preparation process of flexible temperature-pressure sensor and samples. a Process for the preparation of polyacrylonitrile fiber mats. b Fabrication and assembly of flexible temperature-pressure sensors. c Samples for application in robotic arms

After electrode fabrication, adhesive patterning, polyacrylonitrile fiber mat placement, and device assembly, a flexible temperature–pressure sensor based on polyacrylonitrile multimodal sensing materials was obtained, as shown in Fig. 2c. In the assembled device, two polyacrylonitrile fiber mat sensing elements were used for temperature and pressure detection, respectively, enabling independent readout of the two physical parameters. The temperature-sensing element operates through the thermoresistive response of the treated polyacrylonitrile fiber mat, while the pressure-sensing element operates through the piezoresistive response of the nanofibrous structure. The fabricated flexible sensors can be mounted onto robotic grippers to monitor the temperature and contact pressure of grasped objects in high-temperature environments.

As shown in the fabrication process in Fig. 2a and the parameter comparison in Table S1, the method of controlling the degree of polyacrylonitrile fiber oxidation using a heat treatment process has a direct impact on its properties. Therefore, polyacrylonitrile fiber mats treated at different temperatures were systematically characterized to determine the appropriate processing condition for temperature–pressure sensing. The samples were treated in air for 30 min at different temperatures, including no treatment, 600 °C, 700 °C, 800 °C, 900 °C, 1000 °C, and 1100 °C. Their microstructures, elemental compositions, mechanical responses, and sensing performances were then compared. As can be seen in Fig. 3, the microstructure of the polyacrylonitrile fiber mats after different thermal treatments was examined using a scanning electron microscope (SEM). As shown in Fig. 3a1–a5, for samples treated below 1000 °C, the fibrous morphology was largely preserved. The fibers remained continuous and interlaced with the filler material, forming a porous block-like structure. In contrast, after treatment at 1100 °C, the fibrous structure was severely damaged, and only the residual filler framework was observed (Fig. 2a6).

Fig. 3.

Characterizations of polyacrylonitrile fibers. a Polyacrylonitrile fibers at different heat treatment temperatures observed by SEM. b Elemental analysis of polyacrylonitrile fibers by EDS

Energy-dispersive spectroscopy (EDS) analysis further confirmed this structural evolution. As shown in Fig. 3b1, b2, there is no discernible change in the microstructure of the material during thermal treatment below 1000 °C. Furthermore, elemental analysis indicates that the fibers consist of carbon, nitrogen, and oxygen, whilst the filler material comprises silicon and oxygen. However, after treatment at 1100 °C, only silicon and oxygen remain in the EDS figure of the material in Fig. 3b3. The results indicate that following treatment at 1100 °C, all fibers in the material have oxidized and volatilized. At the same time, the ‌X-ray diffraction‌ (XRD) pattern shown in Fig. S1a indicates that, following heat treatment at temperatures exceeding 1000 °C, the amorphous peaks characteristic of the amorphous phase tend to flatten out. At the same time, as shown in Fig. S1b, Raman spectroscopy tests were carried out on polyacrylonitrile fiber mats with different heat treatment temperatures. The laser wavelength is 532 nm, and the scanning range is 600 cm⁻¹~2300 cm⁻¹. As the heat treatment temperature of the material increased, the ratio of the area of the D peak to that of the G peak gradually decreased from 1.71 to 1.01. This series of phenomena indicates that polyacrylonitrile gradually transforms from an insulating polymer into a ladder-like cyclized polymer, graphite-like nanocarbon, and gaseous carbon atoms. The core driving force behind this is the cyclisation, dehydrogenation, and aromatization reactions that occur at high temperatures involving the highly polar cyano group (—C≡N), which is characteristic of polyacrylonitrile. Each repeating unit on the original polyacrylonitrile molecular chain is linked to a highly polar cyano group. The carbon-nitrogen triple bond in the—C≡N group results in a pair of unpaired electrons on the nitrogen atom that do not participate in bonding. These cyano groups are arranged periodically along the molecular chain. As the polyacrylonitrile macromolecular chain adopts an irregular helical conformation, the molecular chains stack to form a quasi-crystalline structure that is laterally two-dimensionally ordered but longitudinally disordered. The π electrons are confined within individual —C≡N groups and cannot delocalize along the chain, resulting in an extremely low carrier concentration; consequently, the material behaves as an insulator, as shown in Table S1. During heat treatment, polyacrylonitrile gradually carbonizes. At the onset of carbonization, adjacent cyano groups undergo intramolecular and intermolecular cyclisation; the π bonds of the —C≡N groups open to form connections, resulting in a ladder-like polymer structure containing pyridine and isoindoline rings. This step causes the previously isolated π electrons to become delocalized within the rings, whilst the lone pair of electrons on the nitrogen atoms participates in conjugation, leading to a sharp rise in carrier concentration, causing the material to transition from an insulator to a conductor. As the temperature rises further, polyacrylonitrile undergoes dehydrogenation, denitrogenation, and aromatization, with the further elimination of small molecules such as H₂, HCN, and NH₃. sp³ carbon gradually converts to sp² carbon, and six-membered aromatic rings continuously fuse and grow, forming graphite-like microcrystals. The delocalization of π electrons extends from individual rings to the entire microcrystalline domain, and the conductive pathways are progressively refined. Upon reaching temperatures above 900 °C, the carbon content of the polyacrylonitrile fibers increases following carbonizations. The sp² carbon network becomes highly developed, the conjugated network becomes highly ordered, and electrical conductivity improves significantly. At temperatures above 1100 °C, the carbon in polyacrylonitrile sublimes significantly, and a large number of atoms (N, H, O) escape in the form of HCN, NH₃, CO, and others. When the temperature exceeds 1100 °C, almost all residual heteroatoms are removed; the thermal vibrational energy of the sp² network overcomes the C–C bond energy, causing the nanocarbon structure to undergo direct solid-state sublimation. The fiber mass rapidly drops to zero, leaving only the filler material, silicon dioxide, within the structure.

To evaluate the compression behavior of the treated polyacrylonitrile fiber mats, in-situ SEM observation was conducted during mechanical loading, as shown in Fig. 4a–d. A schematic diagram of the compression process is shown in Fig. 4e. Taking the sample treated at 700 °C (Fig. 4a1–a3) as an example, in the absence of external pressure, the sample in Fig. 4a1 exhibits a loose morphology, with a large number of incompletely bonded particles and macroscopic pores; the voids between the fibers and particles are clearly visible. Following 150 µm of compressive deformation, as shown in Fig. 4a2, the bonding strength between particles increases, porosity is significantly reduced, and morphological uniformity is markedly improved; following 300 µm of compressive deformation, as shown in Fig. 4a3, the cross-section becomes further densified. Samples heat-treated at 800 °C, 900 °C, and 1000 °C exhibit the same pattern. However, as shown in Fig. 4d1–d3, excessively high heat treatment temperatures reduced the Young’s modulus of the fiber mat, resulting in a significant increase in the number of fibers within the same compressed thickness. Similarly, a similar phenomenon is observed in macroscopic mechanical testing.

Fig. 4.

In situ observation of the compression process of polyacrylonitrile fiber mats. a Heat treatment at 700 °C. b Heat treatment at 800 °C. c Heat treatment at 900 °C. d Heat treatment at 1000 °C. e Schematic diagram of the compression process

As shown in Fig. 5a, for polyacrylonitrile fiber mats of the same dimensions (10 mm × 10 mm × 2.5 mm), the deformation gradually increases with increasing thermal treatment temperature (from no treatment to 1000 °C) under the same applied load. Under a load of 25 N, the untreated polyacrylonitrile fiber mat exhibits a deformation of ~0.4 mm, whereas the sample treated at 1000 °C deforms by as much as 0.7 mm. This result indicates that the elastic modulus of the polyacrylonitrile fiber mat decreases with increasing treatment temperature, thereby reducing its resistance to deformation. This phenomenon is particularly pronounced when the heat treatment temperature exceeds 800 °C. The pressure-sensing performance of polyacrylonitrile fiber mats treated at different temperatures is presented in Fig. 5b–d. The sample treated at 700 °C exhibited the highest sensitivity over the pressure range of 0–480 kPa. This performance can be attributed to the retained fibrous stiffness and loose porous structure, which allow new conductive contact points to form effectively under applied pressure. With increasing treatment temperature, the initial conductivity of the polyacrylonitrile fiber mats increased, but the relative current variation under the same pressure decreased because more conductive pathways had already formed at low pressure. As can be seen from Fig. 5b, c, the polyacrylonitrile fiber mat treated at 700 °C exhibits the highest pressure sensitivity, at 0.78 kPa⁻¹. Furthermore, the polyacrylonitrile fiber mat treated at 1000 °C produces the highest output current (with an input voltage of 1 V and a size of 10 mm × 10 mm × 2.5 mm). Ultimately, based on the combined consideration of mechanical properties and pressure sensitivity, the polyacrylonitrile fiber mat treated at 700 °C for 30 min was selected for pressure sensing. The output curve of the pressure sensor is shown in Fig. 5d. At room temperature and a pressure of 480 kPa, the maximum output current is 59.3 μA. Fig. 5e, f show the pressure repeatability and stability tests performed on the polyacrylonitrile fiber mat. Pressure tests were conducted on the polyacrylonitrile fiber mat under various loading conditions, and it consistently demonstrated good output characteristics.

Fig. 5.

Testing of the mechanical properties of polyacrylonitrile fiber mat. a Deformation characteristics of polyacrylonitrile fiber mat at different heat treatment temperatures. b The sensitivity performance of different polyacrylonitrile fiber mats. c The output current of different polyacrylonitrile fiber mats during full-scale loading. d The output current of polyacrylonitrile fiber mats with 700 °C@30 min during full-scale loading. e The stable and multiple response signals of the polyacrylonitrile fiber mats under different pressures. f Response characteristics of polyacrylonitrile fiber mat under different pressures

The thermal properties of the polyacrylonitrile fiber mat were investigated using a tube furnace as the heat source and a standard K-type thermocouple as the reference temperature source. As shown in Fig. 6a, the current response of the polyacrylonitrile fiber mat exhibits a one-to-one relationship with temperature over the range from room temperature to 432 °C. In stability testing, as shown in Fig. 6b, the polyacrylonitrile fiber mat was able to undergo continuous temperature measurement at temperatures below 300 °C. As shown in Fig. 6c, at 300 °C, the maximum current drift rate was 0.34/min. When subjected to cyclic temperature loading tests ranging from room temperature to 300 °C, the polyacrylonitrile fiber mat demonstrated good temperature measurement stability. According to the calculation results of the data, the maximum standard deviation of three cycles is 2.2, and the repeatability error calculated is ±3.91%. In Fig. 6d, e, the polyacrylonitrile fiber mat was subjected to combined temperature and pressure testing. When subjected to a temperature range of room temperature to 300 °C and a pressure range of 0–200 kPa, the polyacrylonitrile fiber mat exhibits corresponding trends in current output for different pressures and temperatures. At temperatures above 180 °C and pressures above 150 kPa in Fig. 6f, the simultaneous application of temperature and pressure causes the polyacrylonitrile fiber mat to lose structural integrity, resulting in a decline in the rate of current change.

Fig. 6.

Testing of the temperature and mechanical properties of polyacrylonitrile fiber mat. a Temperature response characteristics of the polyacrylonitrile fiber mat with 700 °C@30 min. b The polyacrylonitrile fiber mat output characteristics under different temperature loads. c Temperature cycling test. d, e, f Conduct synchronous loading tests on the polyacrylonitrile fiber mat at different temperatures and forces

The mechanical durability and response speed of the sensor were evaluated, as shown in Fig. 7. Figure 7a illustrates the remarkable stability of the sensor’s current across more than 10,000 loading and unloading cycles under an applied pressure of 150 kPa, highlighting excellent stress tolerance and stability. The repeatability error of the sensor is below 0.96%. Figure 7b presents the response and recovery time of the sensor for the loading and unloading cases under an applied pressure of 100 kPa. The square step-shape response in the graph indicates an extremely fast response time of 53.2 ms and an average recovery time of 8.8 ms^31–35. Figure 7c, d present the response and recovery time of the sensor for the loading and unloading cases at 100 °C/200 °C. When temperature and pressure were applied simultaneously, the loading response times were 105.3 ms and 113.6 ms respectively. The unloading response times were 7.7 ms and 8.1 ms, respectively.

Fig. 7.

Mechanical fatigue testing and response speed testing of sensors. a The signal recording results of the sensor in 10,000 cycles with loading and unloading of 150 kPa. b The response time of the sensor to loading (b₂) and unloading (b₁) forces at room temperature. c The response time of the sensor to loading and unloading forces at 100 °C. d The response time of the sensor to loading and unloading forces at 200 °C

To demonstrate the scalability of the polyacrylonitrile-based sensing strategy, flexible array-type pressure sensors were fabricated using two methods, as shown in Fig. 8. In the first method, as shown in Fig. 8a–c, laser in-situ processing was applied directly to the polyacrylonitrile fiber mat to form an 8 × 8 array of sensing units. Sixty-four pressure-sensing units, each with a size of 6.5 mm × 6.5 mm, were patterned within an area of 90 mm × 90 mm. During laser processing, the laser power was 8 W and the scanning speed was 25 mm/s. The electrical connections of the array sensor are shown in Fig. S2. Only the areas treated by the laser are conductive. An arrayed sensing circuit based on polyimide is employed to acquire the pressure sensing signals. As can be seen from the results in Fig. 8b, c, the fabricated array unit is capable of distinguishing between different external pressure loads. In the second method, the polyacrylonitrile fiber mat was first cut into individual sensing units by laser processing and then thermally treated in a tube furnace, as shown in Fig. S3. The assembled array of pressure sensors is capable of recognizing pressure stimuli corresponding to letters of different shapes (“X”, “J”, “T” and “U”), as shown in Fig. 8d. The thickness and square resistance of each unit were measured using a spiral positioner and a four-point probe analyzer. As shown in Fig. S6, the thickness of the 64 units ranges from 1.15 mm to 1.25 mm. The square resistance values of the 64 units range from 0.43 kΩ·□⁻¹ to 1.50 kΩ·□⁻¹. The test results indicate that the physical properties of the laser-treated polyacrylonitrile fiber mat exhibit good consistency.

Fig. 8.

Fabrication and testing of array-type pressure sensors. a Employing laser oxidation to treat the polyacrylonitrile fiber mat in situ, an 8 × 8 array of sensing units is formed directly. b Test experiment diagram. c Stress testing and results. d Assembled 8 × 8 array pressure sensors using laser cutting and test results

At the same time, laser etching is also used to fabricate flexible temperature-sensing units. As shown in Fig. 9a, the carbon dioxide laser etched various patterns and depths, which can be achieved by altering the pattern and varying the number of processing cycles. By altering the ratio of S_a to S_c and the height of L_b, we can produce flexible temperature-sensing units with varying levels of support. As shown in the test results in Fig. 9b1, the resistance of the patterned flexible temperature sensor is not affected by external pressure. However, when a heated weight was placed on the sensor’s surface, the sensor responded to the temperature in Fig. 9b2. Similarly, by employing different structural designs (the ratio of S_a to S_c), different numbers of processing cycles, or power levels (the height of L_b), it is possible to produce a series of in-situ flexible temperature sensors suitable for different pressure ranges. Sample images are presented in Fig. 9c and Fig. S4. In Fig. 9d, laser-processed flexible pressure and temperature sensors are mounted on the grippers, and gripping tests are conducted on objects at different temperatures under varying pressures. In a series of tests, the flexible pressure sensor is capable of delivering consistent pressure responses across a range of temperatures. With the assistance of a flexible temperature sensor, it is possible to subsequently decouple temperature and pressure.

Fig. 9.

Temperature and pressure testing of sensors. a Fabrication of temperature sensing units using laser etching. b Pressure and temperature testing of the temperature unit. c Pattern designs for temperature sensor units with different structures. d Testing of robotic grippers under varying temperatures and pressures

Conclusion

In this work, a flexible temperature–pressure sensor based on polyacrylonitrile fiber mats was developed for wide-temperature-range multimodal sensing. Through laser in-situ processing or thermal treatment, the electrical properties of polyacrylonitrile fiber mats were effectively regulated, enabling the treated material to serve as both a thermoresistive temperature-sensing element and a piezoresistive pressure-sensing element. The assembled sensor achieved reliable temperature monitoring over 25–300 °C and pressure sensing over 0–480 kPa, showing fast response, good repeatability, and stable performance under cyclic loading. The fabrication strategy was extended to array-type pressure sensing and laser-patterned temperature sensing, confirming the scalability and structural design flexibility of the proposed approach. The integration of the flexible sensing units with robotic grippers further verifies their capability for simultaneous temperature and pressure perception in high-temperature manipulation scenarios. Overall, this polyacrylonitrile-based flexible temperature–pressure sensor provides a feasible strategy for real-time multiparameter monitoring in high-temperature environments. It shows promising potential for lithium-ion battery thermal management, industrial equipment condition monitoring, and emergency rescue applications.

Conflict of interest

The authors declare no competing interests.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1038/s41378-026-01452-5.