A new strategy to tailor the structure of sustainable 3D hierarchical porous N-self-doped carbons from renewable biomass for high-performance supercapacitors and CO2 capture

Abstract

Hierarchical porous N-doped carbons show great potential applications in energy storage and CO₂ capture. Renewable biomass chitosan, which is abundant and simultaneously contains large amounts of N and C, is an ideal alternative to fossil resources for sustainable and scale-up production of cost-effective N-self-doped carbons. In this work, we employed a new and effective strategy to obtain 3D hierarchical porous N-self-doped carbons from chitosan. The hierarchical porous structure of the N-self-doped carbons could be easily tailored to obtain nanorod interconnected and fiber-wall interconnected architectures without using any porogen, catalyst or activator. The nanorod interconnected porous carbon displayed a high specific surface area of 1408 m² g⁻¹ while the fiber-wall interconnected porous carbon exhibited an excellent specific capacitance of 261 F g⁻¹ (0.5 A g⁻¹) due to the desirable hierarchical framework. In addition, these hierarchical porous carbons had a good CO₂ capture performance (3.07–3.44 mmol g⁻¹ at 25 °C). This unique method is supposed to be a new strategy to create novel 3D hierarchical porous carbons for promising applications in supercapacitors, lithium ion batteries, fuel cells and sorbents.