Recent advances on silica-based nanostructures in photocatalysis

Development of highly efficient photocatalysts has emerged as a research hotspot because of their crucial role in affecting the conversion efficiency of solar energy for applications in resource exploitation and environmental purification. The photocatalytic performance of the photocatalysts basically depends on the behaviors of light absorption, charge generation and separation, surface property and structural stability. Owing to its unique advantages (high surface area, tunable porosity, modifiable surface), porous silica provides an interesting platform to construct well-defined nanostructures such as core-shell, yolk-shell and other specific structures which effectively improved one or more of the above behaviors for photocatalysis. Typically, the structure with hollow morphology favors the light scattering and enlargement of surface area, while coating or binding with silica can modify the surface property of a photocatalyst to enhance the surface adsorption of reactants and physicochemical stability of catalysts. This review discusses the recent advances in the design, synthesis, formation mechanism of well-defined silica-based nanostructures, and the achievements of desired physicochemical properties for regulating the photocatalytic performance.