Constructing ZnSe/CoSe2/N-doped carbon composite with multiple heterointerfaces using a solvent-assisted strategy to enhance lithium storage

• Published in: Journal of alloys and compounds 2024-10, Vol.1001, p.175129, Article 175129
• Main Authors: Feng, Ting, Wang, Fang, Cheng, Shaojuan, Tang, Chunjuan, Li, Jili, Yang, Tianxiang, Yi, Jingguang, Wu, Haitao, Xiong, Yi, Ren, Fengzhang
• Format: Article
• Language: English
• Subjects: Heterointerface; Homogeneous heterojunction; Lithium ion batteries; MOFs; ZnSe/CoSe2
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2024.175129

Interface engineering, as an effective strategy for preparing high power density and long-life battery anodes, can promote the electrochemical performance of materials. Herein, metal organic frameworks (MOFs) derived N-doped carbon nanosheets loaded nanoscale ZnSe/CoSe2 particle composite with multiple heterointerfaces is fabricated by solvent assisted strategy. Wherein the content of water in the solvent is a key factor in establishing a homogeneous heterojunction containing cubic phase CoSe2 (c-CoSe2) and orthorhombic phase CoSe2 (o-CoSe2). The built-in electric field generated by the energy band gap difference between ZnSe and CoSe2 or c-CoSe2 and o-CoSe2, and a strong interaction between ZnSe/CoSe2 particles and N-doped carbon nanosheets, can reduce the migration barrier of Li+ at the interface, accelerate charge transfer, and promote the lithium storage kinetic process. In addition, nanoscale ZnSe/CoSe2 particles coupled with N-doped carbon nanosheets can also generate more active sites, reduce volume expansion, and maintain the structural integrity of the anode material. Based on the above structural advantages, the prepared ZnSe/CoSe2-3# exhibits a high reversible capacity (1188 mAh g−1 after 280 cycles at 0.5 A g−1), and excellent long-term cycling stability (788 mAh g−1 at 1 A g−1 over 600 cycles). ●Construction of multiple heterointerfaces by a solvent-assisted strategy.●Homogeneous heterojunctions (c/o-CoSe2) and heterogeneous heterojunctions (ZnSe/CoSe2) coexist.●Strong interface effect improves conductivity and rate performance.●Carbon coating and small-sized particles synergistically alleviate volume expansion and enhance structural stability.●The ZnSe/CoSe2-3# exhibits excellent electrochemical performance in LIBs.