Vertical graphene/Ti2Nb10O29/hydrogen molybdenum bronze composite arrays for enhanced lithium ion storage

The advancement of lithium ions batteries (LIBs) largely relies on the innovation of electrode materials with high power/energy densities, which are highly related to electrode structure and interface characteristics between electrolyte and electrode. In this work, for the first time, we realize the rational integration of titanium niobium oxide (Ti2Nb10O29, TNO) and vertical graphene (VG) into free-standing arrays with intimate core/shell structure. More excitingly, to make the above VG/TNO more perfect, hydrogen molybdenum bronze (HMB) is controllably introduced as a conductive shell to form the ultimate VG/TNO/HMB core/shell composite arrays (CSCAs). VG and HMB serve as powerful conductive body guards for TNO guest, both inside and out. With the enhanced conductivity and reinforced structural stability, the VG/TNO/HMB CSCAs are demonstrated with excellent lithium ion storage performance with higher capacities (317 mAh g(-1) at 2 C, and 163 mAh g(-1) at 60 C), and better cycling life and superior high-rate capability to VG/TNO counterpart. Our findings may offer a promising prospect for construction of advanced high-rate electrodes for electrochemical energy storage.