Polyacrylonitrile Block Copolymers for the Preparation of a Thin Carbon Coating Around TiO 2 Nanorods for Advanced Lithium‐Ion Batteries

Herein, a new method for the realization of a thin and homogenous carbonaceous particle coating, made by carbonizing RAFT polymerization derived block copolymers anchored on anatase TiO 2 nanorods, is presented. These block copolymers consist of a short anchor block (based on dopamine) and a long, easily graphitizable block of polyacrylonitrile. The grafting of such block copolymers to TiO 2 nanorods creates a polymer shell, which can be visualized by atomic force microscopy (AFM). Thermal treatment at 700 °C converts the polyacrylonitrile block to partially graphitic structures (as determined by Raman spectroscopy), establishing a thin carbon coating (as determined by transmission electron microscopy, TEM, analysis). The carbon‐coated TiO 2 nanorods show improved electrochemical performance in terms of achievable specific capacity and, particularly, long‐term cycling stability by reducing the average capacity fading per cycle from 0.252 mAh g –1 to only 0.075 mAh g –1 .