Synthesis of efficient silica supported TiO2/Ag2O heterostructured catalyst with enhanced photocatalytic performance

Abstract

We develop the n-type TiO2 coated on SiO2 support abbreviated as SiO2/TiO2 (ST) followed by deposition of p-type Ag2O nanoparticles outside for the purpose of photocatalytic degradation of organic pollutants. Different composite catalysts were prepared with changing the amount AgNO3 (such as 0%, 5%, 10%, 20%, and 30%) and the composites were abbreviated as ST, STA-5, STA-10, STA-20, and STA-30, respectively. The composite catalysts were characterized with different techniques and tested for Rhodamine B (RhB) dye degradation under UV and visible light. Among the composite catalysts, the degradation efficiency of STA-20 was the highest and it degraded about 99% within 40min under UV light-irradiation. However, the ST, STA-5, STA-10, and STA-30 composite catalysts could degrade about 21%, 47%, 58%, and 75% of the dye, respectively. Furthermore, the STA-5, STA-10, STA-20, and STA-30 composites were also tested and about 39%, 47%, 57%, and 42% of the dye, respectively, was degraded under visible light source. Hence, the formation of p–n junction heterostructure between n-type TiO2 and p-type Ag2O could enhance the degradation of RhB in both UV and visible light irradiation. It could be also potentially applicable photocatalyst for environmental remediation.