General Synthesis of Heteroatom-Doped Hierarchical Carbon toward Excellent Electrochemical Energy Storage

Heteroatom-doping is an effective approach to modify the microstructure of carbon-based materials toward enhanced electrochemical energy storage performance. Nevertheless, it is a great challenge to obtain a specific heteroatom-doped carbon material with hierarchical structure as a general doping strategy is missing. Herein, carbon materials doped with P, S and both of them are designed and precisely prepared through in-situ polymerization. Used as anode for sodium-ion batteries, the best performing material displays a high specific capacity of 368.6 mAh g(-1) at a current density of 0.1 A g(-1) after 100 cycles. A high capacity of 159.8 mAh g(-1) is achieved at a large current density of 5 A g(-1). Impressively, this material also delivers robust storage performances for lithium. According to the first-principles method and detailed experimental data, the expanded interlayer distance and enhanced electronic conductivity of the microcrystalline region can be attributed to C-S and P-C bonds, while the high surface capacitance contribution can be assigned to surface C-S species and highly exposed edges of the microcrystalline region. This work sheds light on a promising method for the exploitation of versatile heteroatom modified hierarchical carbon materials.