Table 5. Comparison of Carbon-Based Materials’ Synthesis Approaches^a.

Synthetic approach	Advantages	Disadvantages
Catalytic pyrolysis	(i) Low temperature and energy requirement	(i) High cost of catalyst
	(ii) Controlled composition of the product	(ii) Low yield of the product
CVD	(i) High growth rate	(i) Complicated process
	(ii) Good yield of product	(ii) high-temperature requirement
	(iii) Better option for the development of the epitaxial thin film
Pyrolysis deposition CVD	(i) Simple and facile	(i) Structure destruction during the template etching technique
	(ii) Reuse of plastic with a lower amount of solvent
	(iii) Ordered porous structure
Thermal decomposition	(i) Material with controlled pore size, high surface area, and conductivity	(i) High temperature results in large pore volume, low energy density, and conductivity
Activation method	(i) One-pot process with low-temperature requirement	(i) Low product purity
	(ii) Ordered structure with good porosity and high surface area	(ii) Large volume of water required for washing purpose
Template-based method	(i) Highly ordered structure	(i) Structure collapse or disorder
		(ii) Pore blockage during etching
Hydrothermal carbonization	(i) Simple approach to get valuable materials with oxygen functionalities	(i) High cost and undeveloped porosity
One-pot synthesis	(i) Simple, affordable, and reproducible nature of the process	(i) Polymer amount and the nature of the reactor
Thermochemical conversion	(i) Fast conversion rate	(i) High temperature
	(ii) High surface area	(ii) Uncontrolled morphology
	(iii) Environmentally benign product by complete conversion of organic parts into carbon-based materials
Stepwise cross-linking	(i) Favorable technique for the fabrication of a thermally stable cross-linked structure	(i) Partial deterioration of structure upon heating
		(ii) Moderate porosity

^aHere is a comparison of different techniques utilized for the synthesis of carbonaceous materials such as activated carbon, graphene, and carbon nanotubes.