Polyrrole-encapsulated Cu2Se nanosheets in situ grown on Cu mesh for high stability sodium-ion battery anode

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2022-04, Vol.433, p.134477, Article 134477
• Main Authors: Yue, Luchao, Wang, Dong, Wu, Zhenguo, Zhao, Wenxi, Ren, Yuchun, Zhang, Longcheng, Zhong, Benhe, Li, Na, Tang, Bo, Liu, Qian, Luo, Yonglan, Asiri, Abdullah M., Guo, Xiaodong, Sun, Xuping
• Format: Article
• Language: English
• Subjects: Cu2Se@PPy anode; Cycle stability; Metal selenides; Sodium-ion battery
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2021.134477

PPy-encapsulated Cu2Se nanosheetsin-situ grown on the Cu mesh (Cu2Se@PPy) acts as a high-performance anode for sodium-ion batteries, capable of delivering a high specific capacity of 293.0 mAh g−1 at 1.0 A g−1, impressive rate capacity of 263.5 mAh g−1 under 10.0 A g−1 over 2000 cycles. [Display omitted] •Cu2Se nanosheets were in-situ grown on Cu mesh at room temperature.•PPy coating layer enables robust structure stability and fast charge transport.•Cu2Se@PPy as a SIBs anode gives high specific capacity.•Cu2Se@PPy as a SIBs anode offers outstanding cycling durability. Copper selenide (Cu2Se) features high theoretical capacity and quasi-2D characteristics built by repeating sextuple layers of Se-Cu-Cu-Cu-Cu-Se, making it a fascinating anode for sodium-ion batteries (SIBs). However, it experiences huge volume variation during repeated discharge–charge processes. Here, a productive approach to preserve the structure of Cu2Se anode via in-situ coating conductive polymer carbon is proposed. As a demonstration, Cu2Se nanosheets encapsulated by polypyrrole (PPy) were anchored on Cu mesh (Cu2Se@PPy) and regarded as an electrode material for SIBs. The PPy shell enjoys double functions that improves the electronic conductivity as well as alleviates the significant volume swelling of Cu2Se. As a result, Cu2Se@PPy gives a satisfactory electrochemical performance, including high specific capacity of 293.0 mAh g−1 at 1.0 A g−1, impressive rate capacity (263.5 mAh g−1 under 10.0 A g−1 over 2000 cycles). This work describes the uncomplicated approaches available for designing high stability metal selenides anodes for sodium storage.