Main content area

A General and Facile Approach to Heterostructured Core/Shell BiVO4/BiOI p–n Junction: Room-Temperature in Situ Assembly and Highly Boosted Visible-Light Photocatalysis

Huang, Hongwei, He, Ying, Du, Xin, Chu, Paul K., Zhang, Yihe
ACS sustainable chemistry 2015 v.3 no.12 pp. 3262-3273
ambient temperature, electrochemistry, energy, free radicals, irradiation, models, monitoring, nanosheets, phenol, photocatalysis, photocatalysts, semiconductors, superoxide anion
Development of core/shell heterostructures and semiconductor p–n junctions is of great concern for environmental and energy applications. Herein, we develop a facile in situ deposition route for fabrication of a BiVO₄/BiOI composite integrating both the core/shell heterostructure and semiconductor p–n junction at room temperature. In the BiVO₄/BiOI core/shell heterostructure, the BiOI nanosheets are evenly assembled on the surface of the BiVO₄ cores. The photocatalytic performance is evaluated by monitoring the degradation of the dye model Rhodamine B (RhB), colorless contaminant phenol, and photocurrent generation under visible-light irradiation. The heterostructured BiVO₄/BiOI core/shell photocatalyst shows drastically enhanced photocatalysis properties compared to the pristine BiVO₄ and BiOI. This remarkable enhancement is attributed to the intimate interfacial interactions derived from the core/shell heterostructure and formation of the p–n junction between the p-type BiOI and n-type BiVO₄. Separation and transfer of photogenerated electron–hole pairs are hence greatly facilitated, thereby resulting in the improved photocatalytic performance as confirmed by electrochemical, photoelectrochemical, radicals trapping, and superoxide radical (•O₂–) quantification results. Moreover, the core/shell BiVO₄/BiOI also displays high photochemical stability. This work sheds new light on the construction of high-performance photocatalysts with core/shell heterostructures and matchable band structures in a simple and efficient way.