高CO₂選択性を有する太陽光駆動型光触媒によるトリクロロエチレンの鉱化

Sunlight-driven photocatalytic oxidation, using ambient air as the oxidant, offers a sustainable route for removing chlorinated volatile organic compounds (VOCs) such as trichloroethylene (TCE). Yet, practical implementation is hindered by low reaction rates and undesirable product selectivity. Here, we present a material design strategy that overcomes both challenges. Size-controlled anatase TiO₂ nanocrystals with truncated bipyramid (nanoTBP) morphology achieve exceptional photocatalytic activity for TCE degradation, comparable to rates reported for energy-intensive thermal catalysis, with unoptimized CO₂/CO product ratios. Decorating as-synthesized TiO₂ with Pt nanoparticles significantly enhances the CO₂ selectivity but significantly diminishes the overall reaction rates. To resolve this rate-selectivity trade-off, we integrate Pt/TiO₂ with pristine TiO₂ into an optimized composite photocatalyst, unlocking a tandem pathway that enables both rapid degradation and complete mineralization of TCE to CO₂ under solar irradiation. Taken together, this work establishes a scalable, solar-enabled, materials-based strategy for complete gas-phase mineralization of TCE, with broader implications for novel and sustainable VOC treatment processes.