Hierarchical Carbon Nanosheet Assembly with SiOx Incorporation and Nitrogen Doping Achieves Enhanced Lithium Ion Storage Performance

Abstract

Lithium ion batteries (LIBs) have dominated the markets of portable electronics due to the merits of a low self‐discharge rate, high voltage platform, environmental friendliness, and portability. However, the limited theoretical capacity of the current commercial anode material causes unsatisfied energy density of LIBs, which falls behind the ever‐increasing demands of society. Herein, a hierarchical porous carbon nanosheet assembly is successfully constructed with simultaneous SiOx incorporation and nitrogen doping (denoted as HPCNA‐(N, Si)) through a supramolecular assembly–based one‐pot strategy followed by a calcination process. Benefitting from the unique morphology, highly porous feature, and the synergy of SiOx incorporation and nitrogen doping, the HPCNA‐(N, Si) exhibits largely enhanced Li+ storage performance when evaluated as anode material for LIBs. Specifically, it can deliver a high specific capacity of 583.0 mA h g−1 at 500 mA g−1 with a stable cycling capability (700 cycles with an average attenuation rate of 0.32% at 1000 mA g−1). The possible origins of the promising Li+ storage behavior for HPCNA‐(N, Si) are unraveled based on the cyclic voltammetry (CV) curves, where a fair capacitive contribution of 63.6% at 0.9 mV s−1 could imply fast ion transfer kinetics for superior rate and cycling performance.

Keywords

• anodes
• carbon
• lithium ion batteries
• nitrogen doping
• porous structure