Abstract
As one of the most promising semiconductor oxide materials, titanium dioxide (TiO(2)) absorbs UV light but not visible light. To address this limitation, the introduction of Ti(3+) defects represents a common strategy to render TiO(2) visible-light responsive. Unfortunately, current hurdles in Ti(3+) generation technologies impeded the widespread application of Ti(3+) modified materials. Herein, we demonstrate a simple and mechanistically distinct approach to generating abundant surface-Ti(3+) sites without leaving behind oxygen vacancy and sacrificing one-off electron donors. In particular, upon adsorption of organodiboron reagents onto TiO(2) nanoparticles, spontaneous electron injection from the diboron-bound O(2-) site to adjacent Ti(4+) site leads to an extremely stable blue surface Ti(3+)‒O(-·) complex. Notably, this defect generation protocol is also applicable to other semiconductor oxides including ZnO, SnO(2), Nb(2)O(5), and In(2)O(3). Furthermore, the as-prepared photoelectronic device using this strategy affords 10(3)-fold higher visible light response and the fabricated perovskite solar cell shows an enhanced performance.