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.