Carbon Dot-Modified TiO2@SiO2 Aerogel as an Anode for Lithium-Ion Batteries

Abstract

Titanium oxides have been considered promising anode materials for lithium-ion batteries (LIBs). However, the poor conductivity and low specific capacity of bulk titanium oxides limit their application. In this study, a carbon dot-modified TiO2@SiO2 aerogel was successfully fabricated through a facile ambient pressure drying strategy and used as an anode material of LIBs. Benefiting from the crosslinking of carbon dots and the surface modification of SiO2, the as-prepared hierarchical aerogel exhibited a high initial discharge capacity of 974 mAh g−1 and maintained a capacity of 299 mAh g−1 after 100 cycles at 0.1 A g−1. It also retained a discharge capacity of 111 mAh g−1 with a CE of 99.9% at 3 A g−1. The carbon dot-modified cross-linking skeleton contributes to the structural integrity of the TiO2@SiO2 aerogel during repeated insertion/extraction of lithium ions, guaranteeing outstanding cycling and high-rate performance. This ambient pressure drying strategy provides a facile and feasible way to produce high-performance aerogel anode materials for lithium-ion storage.