Crack-Free and Thickness-Controllable Deposition of TiO₂–rGO Thin Films for Solar Harnessing Devices

The use of thin films consisting of TiO₂ and reduced graphene oxide (TiO₂ –rGO) in solar harnessing devices is gaining momentum thanks to improved charge-transporting characteristics. In this report, we propose a facile spin-coating methodology for the deposition of crack-free and thickness-controllable TiO₂ –rGO thin films. A range of characterization techniques were utilized to confirm the formation of the TiO₂ –rGO thin film. Improved charge-transporting properties of TiO₂ –rGO composite thin films were confirmed by measuring their photoelectrochemical (PEC) activity under simulated solar light illumination. In particular, it was found that the TiO₂ –rGO composite thin film yielded a better photocurrent response (~151.3 µA/cm²) than the bare TiO₂ thin film (~71.6 µA/cm²) at 1.23 eV vs. the reversible hydrogen electrode (RHE). The obtained results suggested that rGO addition remarkably improves the charge-transporting properties in TiO₂ films.