Bimetal‐Organic‐Framework Derivation of Ball‐Cactus‐Like Ni‐Sn‐P@C‐CNT as Long‐Cycle Anode for Lithium Ion Battery

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 13; no. 27; pp. 1700521 - n/a
• Main Authors: Dai, Ruoling, Sun, Weiwei, Lv, Li‐Ping, Wu, Minghong, Liu, Hao, Wang, Guoxiu, Wang, Yong
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.07.2017
• Subjects: Anode effect; Battery cycles; Bimetals; Carbon; Carbon nanotubes; Catalysis; Derivation; Electric potential; Electrochemical analysis; Irradiation; Ligands; Lithium; Lithium-ion batteries; metal organic frameworks; Nanotechnology; Ni3Sn4; Nickel; NiP2; Phosphides; Rechargeable batteries; NiP2; lithium ion batteries; Ni3Sn4; metal organic frameworks; carbon nanotubes
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.201700521

Metal phosphides are a new class of potential high‐capacity anodes for lithium ion batteries, but their short cycle life is the critical problem to hinder its practical application. A unique ball‐cactus‐like microsphere of carbon coated NiP2/Ni3Sn4 with deep‐rooted carbon nanotubes (Ni‐Sn‐P@C‐CNT) is demonstrated in this work to solve this problem. Bimetal‐organic‐frameworks (BMOFs, Ni‐Sn‐BTC, BTC refers to 1,3,5‐benzenetricarboxylic acid) are formed by a two‐step uniform microwave‐assisted irradiation approach and used as the precursor to grow Ni‐Sn@C‐CNT, Ni‐Sn‐P@C‐CNT, yolk–shell Ni‐Sn@C, and Ni‐Sn‐P@C. The uniform carbon overlayer is formed by the decomposition of organic ligands from MOFs and small CNTs are deeply rooted in Ni‐Sn‐P@C microsphere due to the in situ catalysis effect of Ni‐Sn. Among these potential anode materials, the Ni‐Sn‐P@C‐CNT is found to be a promising anode with best electrochemical properties. It exhibits a large reversible capacity of 704 mA h g−1 after 200 cycles at 100 mA g−1 and excellent high‐rate cycling performance (a stable capacity of 504 mA h g−1 retained after 800 cycles at 1 A g−1). These good electrochemical properties are mainly ascribed to the unique 3D mesoporous structure design along with dual active components showing synergistic electrochemical activity within different voltage windows. Bimetal‐organic frameworks of a Ni‐Sn‐BTC metal organic framework precursor are used to synthesize a unique ball‐cactus‐like Ni‐Sn‐P@C‐CNT microsphere with carbon overlayer and deep‐rooted CNTs. It delivers a large Li‐storage capacity of 704 mA h g−1 after 200 cycles at 100 mA g−1 and excellent high‐rate cycling performance. A capacity of 504 mA h g−1 is retained after 800 cycles at 1 A g−1.