Electrospun porous carbon nanofibers derived from bio-based phenolic resins as free-standing electrodes for high-performance supercapacitors

Phenolic resins were employed to prepare electrospun porous carbon nanofibers with a high specific surface area as free-standing electrodes for highperformance supercapacitors. However, the sustainable development of conventional phenolic resin has been challenged by petroleum-based phenol and formaldehyde. Lignin with abundant phenolic hydroxyl groups is the main non-petroleum resource that can provide renewable aromatic compounds. Hence, lignin, phenol, and furfural were used to synthesize bio-based phenolic resins, and the activated carbon nanofibers were obtained by electrospinning and one-step carbonization activation. Fourier transform infrared and differential scanning calorimetry were used to characterize the structural and thermal properties. The results reveal that the apparent activation energy of the curing reaction is 89.21 kJmiddotmol(-1) and the reaction order is 0.78. The activated carbon nanofibers show a uniform diameter, specific surface area up to 1100 m2middotg(-1), and total pore volume of 0.62 cm3middotg-1. The electrode demonstrates a specific capacitance of 238 Fmiddotg(-1) (0.1 Amiddotg(-1)) and good rate capability. The symmetric supercapacitor yields a high energy density of 26.39 Wmiddothmiddotkg(-1) at 100 Wmiddotkg(-1) and an excellent capacitance retention of 98% after 10000 cycles. These results confirm that the activated carbon nanofiber from bio-based phenolic resins can be applied as electrode material for high-performance supercapacitors.

Automated summary

In this study, bio-based phenolic resins were synthesized using lignin, phenol, and furfural, and activated carbon nanofibers were obtained through electrospinning and one-step carbonization activation. The activated carbon nanofibers exhibited uniform diameter, high specific surface area up to 1100 m2/g, and total pore volume of 0.62 cm3/g. The electrode showed a specific capacitance of 238 F/g (0.1 A/g) and good rate capability. The symmetric supercapacitor achieved a high energy density of 26.39 Wh/kg at 100 W/kg and an excellent capacitance retention of 98% after 10000 cycles. These results indicate that activated carbon nanofibers from bio-based phenolic resins can be applied as electrode materials for high-performance supercapacitors.