Growing Single-Walled Carbon Nanotubes on Silicon-Supported Catalyst as a Composite Anode for Enhanced Lithium Storage
Zhen Wang, Qianru Wu, Chaoxu Hao, Daming Chen, Juan Wang, Haina Ci, Xinxing Wang, Maoshuai He
Abstract
Single-walled carbon nanotubes (SWNTs) are considered to be a class of materials with broad application prospects. Chemical vapor deposition (CVD) enables the direct growth of SWNTs on targeted supports using active metal catalysts. Unfortunately, no work to date has reported silicon (Si) as a viable support for growing SWNTs due to the deactivation of metal catalysts caused by high-temperature reactions with Si. Recent studies show that incorporating SWNTs into Si anodes improves the electrical conductivity and alleviates volume expansion in lithium-ion batteries (LIBs). However, the shear forces during dispersion fragment SWNTs and destroy their pristine electronic properties. This work addresses these challenges by using ruthenium to directly grow SWNTs on Si nanoparticles via CVD, preserving their structural integrity and electrical properties. The resulting composites are employed as an anode for LIBs. Owing to the strong binding between synthesized SWNTs and Si nanoparticles, the resulting composite anode exhibits enhanced electronic/ionic conductivity and suppressed volume expansion during cycling. Consequently, the assembled battery displays a higher initial Coulombic efficiency, excellent rate capability, and cycling stability. This work demonstrates the feasibility of growing SWNTs on Si supports, offering valuable insights for optimizing and advancing the application of Si anodes.