Development of a Photo Oxidation/Reduction Electrode in Photocatalytic Study

Abstract

Catalysis has been a thrust area in materials research and MOFs have shown potential to make strong in-road in catalytic applications. Many of these MOFs reportedly have shown photosensitivity and since photocatalysis constitute one of the most intriguing areas of research within the domain of catalysis, it would be worth an effort to probe their effectiveness as photocatalyst. Although, the success or failure of any MOF compound as photocatalyst would largely depend on their ability to remain stable under aqueous and/or organic medium on prolonged exposure. Transparent conducting oxide (TCO) thin film is a recent concept. Harnessing solar energy has been a thrust area and gaining momentum continually. Various methods, products and technologies have been developed towards this direction and our present research endeavor and motivation is mainly sourced from the issue on harnessing solar energy in photo degradation. In this work, two contemporary metal organic frameworks (MOFs) i.e. MOF-5 (ZnBDC) and MIL-53(Fe) (or, Fe-BDC) were synthesized using microwave synthesis technique and characterized. Transparent conducting oxide (TCO) thin films were fabricated by sol-gel and spin coating techniques. MOF films (Zn-BDC) were grown onto TCO. Improvisations were also made in TCO matrix by using Al and Pb as doping agents. The doping percentage as well as the number of cycles of coating was varied so as to get the most suitable TCO.The performance study of MOFs and ZnO as photocatalyst were carried out in degradation of ammonia. When used directly, MOFs had shown a better degradation percentage (ca. 60%) as compared to ZnO and that could be attributed to their very high specific surface area as compared to ZnO. Meanwhile, TCO films of various combinations when tested for their electrical conductivity are met with limited success and further work is going on towards achieving the targeted results