Amorphous Domains in Black Titanium Dioxide

Although oxygen vacancies (O(v)s) play a critical role for many applications of metal oxides, a controllable synthetic strategy for anisotropic O(v)s remains a great challenge. Here, a novel strategy is proposed to achieve the regional dual structure with anisotropic O(v)s at both the surface and in the interior of TiO2 by constructing amorphous domains. The as-prepared black TiO2 with amorphous domains exhibits superior activity in degrading rhodamine B (RhB) solutions, which can instantly decompose RhB with just a shake. First-principle simulations reveal that subsurface O(v)s in TiO2 are energetically favored, resulting in the formation of amorphous domains in the interior region via diffusion of surface-formed O(v)s into the subsurface. The stable O-v-induced amorphous domains in TiO2 with enhanced catalytic performances provide a scalable strategy to practical O-v engineering in functional metal oxides.

Automated summary

By constructing amorphous domains, researchers have successfully achieved a regional dual structure in TiO2 materials with anisotropic oxygen vacancies, resulting in superior catalytic activity in degrading RhB solutions.