Advances in the Improvement of the Quality and Efficiency of Biomass-Derived Porous Carbon: A Comprehensive Review on Synthesis Strategies and Heteroatom Doping Effects

The biomass porous carbon has recently garnered significant attention in the electrochemical energy storage, which is attributed to the excellent electrochemical performance, cost-effectiveness, abundant and sustainable sources, et al. Unfortunately, the inherent physicochemical property deficiencies of biomass-based porous carbons, such as pore structure, electrical conductivity, and surface wettability, significantly limit their electrochemical performance. Therefore, this paper discusses the regulation of pore structure, catalytic graphitization, and modification of carbon surfaces from three different perspectives: activation, the catalytic action of metal compounds, and heteroatom doping. It reviews the controllable regulation of the porous structure and chemical properties of porous carbon by various activators, especially the specific pore-forming mechanisms. Subsequently, it explores the catalytic mechanism by which metal compounds promote the conversion of amorphous carbon to graphite carbon, as well as the impact of the degree of graphitization on the electrochemical performance of carbon-based materials. Lastly, it discusses the unique electrochemical properties induced by doping with different heteroatoms (N, S, P, and B atoms) and the doping mechanisms, summarizing the specific effects of different heteroatom dopings on the pore structure (pore size distribution, specific surface area, etc.). Additionally, the synergistic effects of multi-atom doping on the porous characteristics, electronic structure, and chemical properties of carbon materials are discussed. Furthermore, this paper reviews the enhancing effects of corresponding modification techniques on the electrochemical energy storage performance. This article presents a comprehensive and in-depth theoretical framework for the improvement strategies of biomass-based porous carbon materials.