Extremely durable supercapacitor enabled by disordered porous carbon with a capacity retention up to 60 000 cycles

Abstract

Carbon-based materials, known for their green sustainability and high specific surface area, have long been favored as electrode materials with commercial prospects. However, they often fall short of delivering the expected performance in areas such as electrical conductivity and cycle stability. This paper reports a porous carbon material formed by combining NaCl crystals and citric acid. Relying on the hard template configuration, the molten pore-forming of NaCl crystals causes the citric acid base material to produce disordered porous carbon. Structural characterization and performance testing reveal that after high-temperature carbonization, the material generates numerous mesopores due to the evaporation etching of NaCl and has amorphous carbon with a highly disordered and dense structure. The resulting high specific surface area and abundant defects endow it with highly efficient electrochemical performance. Moreover, an enhanced specific capacitance of 81 F g⁻¹ at a current density of 0.5 A g⁻¹ and high capacitance retention rate of 98% after 60 000 cycles of the synthesized supercapacitor were obtained. This research offers a new avenue for the development of green energy and the design of electrode materials with commercial potential.