Huge discharge of antibiotics is posing threats to sustainable environment and human health. Semiconductor based photocatalytic techniques have a significant role to play. Effective light absorption and charge carrier separation are the detrimental factors to enhance fine-tuning solar-driven activity of photocatalysts. Introducing surface defects and regulating microstructures can significantly improve photocatalytic activity due to the synergetic effects of rapid depletion of electron−holes, improved light absorption and well-tuned surface interface metrics. Herein, taking advantages of stepwise ionization, tunable compositions of molten salts and combined with the synthetic techniques of crystal growth process, we synthesized a Ti-based perovskite CaCu3Ti4O12 consisting of various exposed facets and surface defects (metal deficiencies and oxygen vacancies) by an environmentally friendly molten salt approach without using structure directing agents. Owning to various exposed facets and tailored morphology, as-obtained CaCu3Ti4O12 catalysts showed high performance for an antibiotic degradation than that its counterparts, defect-free CaCu3Ti4O12. Density functional theory (DFT) calculations and photodecomposition results suggest that existing of exposed facets contribute to spatial separation of photoinduced electron−holes. The obvious differences in photocatalytic performances are ascribed to well-defined crystal facets, effective charge transfer, assorted surface deficiencies and critical roles of active species, all which are the main determinants for antibiotic degradation over as-obtained CaCu3Ti4O12. This facet-defect-based photocatalyst implies an important indication of the effects by exposed facets and various defects for facilitating carrier transformation, promoting carrier lifetime, and enhancing surface-interface reaction. This contribution also deepens the fundamental understanding of preparation and unearthing the crystal facet-based visible light perovskite for environmental applications.

Visible light-driven photocatalytic activity of defective Ti-based perovskites for antibiotic decomposition

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.