Natural leaves-assisted synthesis of nitrogen-doped, carbon-rich nanodots-sensitized, Ag-loaded anatase TiO2 square nanosheets with dominant {001} facets and their enhanced catalytic applications

Extending the UV response of anatase TiO2 photocatalysts into the visible light range can play a pivotal role in promoting the practical applications of these catalysts. Nitrogen and carbon co-doped, silver loaded anatase TiO2 (Ag@NC-TiO2) single-crystal nanosheets dominated by {001} facets were prepared for the first time using leaves as the nitrogen and carbon source by a facile, low cost method. The size of the Ag particles on NC-TiO2 nanosheets can be tuned from 1.5 nm to 15 nm using a photo-reduction strategy. The synthesized Ag@NC-TiO2 nanosheets show higher photocatalytic activity in the photodecomposition of organic pollutants compared to NC-TiO2, TiO2 and P25 under visible light irradiation. The enhanced photocatalytic efficiency was ascribed to a synergistic effect between N, C and Ag. In addition, the formed Ag@NC-TiO2 heteronanosheets are highly dispersible in aqueous solution and are capable of efficient catalysis for the reduction of p-nitrophenol. The present synthesis gives a promising method of forming non-metal co-doped, metal nanoparticles (NPs) loaded anatase TiO2 with dominant {001} facets and for broad applications in catalysis and photocatalysis.