Effect of low energy ion irradiation on TiO$_{2}$-based hybrid nanostructures for enhanced photocatalytic activity

Abstract

Low energy ion-irradiated hybrid nanostructures with altered interfaces have sparked a lot of interest in the field of photocatalytic applications. In context to that, the present work on low energy ion (LEI) irradiation at different fluences is carried out to study the modification in TiO$_{2\, }$hybrids and hence their photocatalytic studies. LEI is carried out using 50 keV of P ions for TiO$_{2}$ nanorods (TiNRs)-based hybrids (Ag-TiNRs and Au-TiNRs) at different fluences to induce structural, morphological, and interfacial changes. It is found that these hybrid nanostructures get modified at low fluence (5X10$^{14\, }$ions/cm$^{2})$, whereas at higher fluence (5X10$^{15\, }$ions/cm$^{2})$, their morphologies are damaged. These changes are studied using Micro-Raman spectroscopy. The analysis revealed that the blue shift in the E$_{g}$ mode of LEI hybrids is attributed to compressive strain, which introduces defects in the TiO$_{2}$ nanostructures. The X-ray photoelectron spectroscopy analysis reveals the formation of the Schottky barrier with a shift towards the lower binding energy and this is credited to interfacial interaction and separation of charges at the interfaces. The effects of structural and interfacial modifications of LEI hybrids are further studied for electrochemical and photocatalytic analyses.