Engineering high-efficient phosphorus-doped TiO2 photocatalyst employed for a sophisticated visible-light driven photocatalytic coating

The application of coatings with various functionality has attracted increasing attention recently. Herein, the disadvantage of black phosphorus (BP), i.e. instability in atmosphere, was elaborately utilized to fabricated a phosphorus-doped titanium dioxide (P-TiO2) composites via the formation P-O-Ti bond. Then, the obtained P-TiO2 composites were blended with polyacrylic matrix to prepare functional coatings with outstanding photocatalytic performance. The polyacrylic coating modified with 1.0 wt% P-TiO2 still achieved 100 % efficiency for formaldehyde removing even after four cycles of photocatalytic degradation experiments, indicating the highly efficiency and great stability of P-TiO2. Additionally, the P-TiO2/polyacrylic coating also achieved a high 57.62 % micronization efficiency as excited by the Ultraviolet (UV) light, while the efficiency for pure polyacrylic and the 1.0 wt% TiO2 dopped sample was only 21.47 % and 26.53 %, further highlighting the indispensable role of P doping. To reveal the underlying mechanism, photocatalytic degradation experiment of 20 mg/L Rhodamine B (RhB) via P-TiO2 was conducted, whose degradation efficiency can still achieve 95.55 % even after 20 cycles of degradation experiments. Further research proved that the formation of P-O-Ti bonds generates new energy level in P-TiO2 to the lower the bandgap, and thus promotes the generation of •OH and •O2− free-radicals in the visible light range, thereby enhancing the photocatalytic performance of TiO2. This research demonstrates a facile but effective strategy to design nanocomposites with high photocatalytic performance and thus promotes the practical applications of multifunctional resin in the field of coatings.