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Modification of TiO₂ Nanoparticles with Organodiboron Molecules Inducing Stable Surface Ti³⁺ Complex.

ABSTRACT: As one of the most promising semiconductor oxide materials, titanium dioxide (TiO₂) absorbs UV light but not visible light. To address this limitation, the introduction of Ti³⁺ defects represents a common strategy to render TiO₂ visible-light responsive. Unfortunately, current hurdles in Ti³⁺ generation technologies impeded the widespread application of Ti³⁺ modified materials. Herein, we demonstrate a simple and mechanistically distinct approach to generating abundant surface-Ti³⁺ sites without leaving behind oxygen vacancy and sacrificing one-off electron donors. In particular, upon adsorption of organodiboron reagents onto TiO₂ nanoparticles, spontaneous electron injection from the diboron-bound O^2- site to adjacent Ti⁴⁺ site leads to an extremely stable blue surface Ti³⁺‒O^-· complex. Notably, this defect generation protocol is also applicable to other semiconductor oxides including ZnO, SnO₂, Nb₂O₅, and In₂O₃. Furthermore, the as-prepared photoelectronic device using this strategy affords 10³-fold higher visible light response and the fabricated perovskite solar cell shows an enhanced performance.

SUBMITTER: Cao Y

PROVIDER: S-EPMC6833477 | biostudies-literature |

REPOSITORIES: biostudies-literature

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