Tunable cobalt doping titanium nitride (TixCoyN) interlaced nanotubes enable an enhanced electronic synergy on visible-light driven hydrogen evolution

Overcoming the limited light harvest and sluggish charge transfer efficiency has remained a long-standing challenge for the practical application of visible-light driven hydrogen evolution . In this work, a novel cobalt doped titanium nitride interlaced nanotube was synthesized through a facile hydrothermal approach and subsequent ammonia gas nitrification route. The optimized Ti 0·75 Co 0·25 N (molar ratio of Ti:Co:N = 0.75:0.25:1) catalyst delivered the highest hydrogen yield in visible-light-induced water splitting, which was almost 2 times higher than the pristine TiN did. Further structure characterizations have unraveled that the cobalt atoms were partially substituted the titanium atoms in crystallite lattice, generating a significant synergistic regulation on band structure and electronic state. As a result, the narrowed energy bandgap, improved charge carrier mobility and lowered over-potential contributed to the high electron-hole separation efficiency and smoothed interface charge transfer, yielding an enhanced photocatalytic activity . This work is a significant contribution to the design of efficient and stable visible light driven water splitting catalysts.