Boron-manganese-nitrogen co-doped three-dimensional porous carbon realizes superior capacitive lithium-ion storage

Three-dimensional (3D) porous carbon has sufficient specific surface area and anchor positioning points. The pore structure facilitates uniform charge distribution, and buffers volume changes during stripping. However, single carbon materials have limited theoretical capacity and short cycle life. Here, 3D porous carbon material BCN/Mn-6 (B,N and Mn co-doped porous carbon with 6 mmol Mn content) co-doped with manganese, boron and nitrogen was synthesized by heat treatment. Affective modulation of the material structure and surface functional groups was achieved by adjusting the amount of manganese doping. The metal element doping can promote the diffusion of lithium ions , and the formed vacancies and defects can be used as lithium storage sites. Nitrogen doping can improve the dispersion and stability of metals and oxides , and regulate the redox capacity. Co-doping of metals and heteroatoms synergistically improves electrical conductivity . Thus, BCN/Mn-6 exhibits excellent cycling stability (99.60 % Coulombic efficiency after 300 cycles) and specific capacity (779.9 mAh/g), and shows capacity rise. This study provides a new direction for the preparation of carbon-based electrode materials doped with heteroatoms and the study of capacitive energy storage mechanisms.