Studying the governing factors on the photo(electro)catalytic activity of surface-modified photocatalysts under visible light illumination

The nature of the interaction at the interface of dye molecules and TiO2 surface has paramount importance in their photosensitization properties for photo(electro)catalytic application. To address this issue, two groups of organic molecules i.e., catechol and salicylic derivatives were used for the surface modification of titania. These hybrid materials were then thoroughly analyzed employing XRD, SEM, UV-Vis, FTIR, Raman, and impedance spectroscopies. The photoactivity was studied using the photoelectrochemical analysis and photocatalytic hy-droxylation of terephthalic acid. Moreover, applying principal component analysis on Raman spectra indicated a significant change in the bond strength of Ti-O (B1g band) as a consequence of the chemical bond of adsorbed dye. This study links the nature of the interaction of dye and titania and the photoactivity of materials, which is thoroughly discussed in the presented work.

Automated summary

In this study, the interaction between dye molecules and the TiO2 surface was investigated for their photosensitization properties in photo(electro)catalytic applications. Two groups of organic molecules, catechol and salicylic derivatives, were used for surface modification of titania. The hybrid materials were thoroughly analyzed using various techniques, such as XRD, SEM, UV-Vis, FTIR, Raman, and impedance spectroscopies. The photoactivity was assessed through photoelectrochemical analysis and photocatalytic hydroxylation of terephthalic acid. The study also revealed a significant change in the bond strength of Ti-O due to the chemical bond of the adsorbed dye, as observed from the principal component analysis of Raman spectra. The nature of the dye-titania interaction and its influence on material photoactivity were extensively discussed in this work.