TiO2/Fe2O3: Type-I Heterostructures for Electrochemical Dye Degradation/Water Splitting Studies

Abstract

In contemporary research, semiconductor composite materials, i.e., combination of different semiconductor materials, play an important role in extracting needful energy from existing renewable energy forms. For example, “heterostructure” composite assemblies facilitate faster charge carrier transport and therefore improve the efficiency of the electro-/photoelectrochemical processes/devices due to synergistic interaction and synchronized charge transport across material interfaces that have formed in composite assembly. Herein, we report type-I heterostructure consists of TiO2 and Fe2O3 for crystal violet dye degradation and water splitting studies via electrochemical route. The rationale in choosing the above materials (TiO2, Fe2O3) in the present study will not only account stability, nontoxicity, and high oxidation power but also facilitate the fast charge carrier movements due to proper band edge alignments. Synthesized TiO2, Fe2O3, and TiO2/Fe2O3 nanoparticle assemblies were fabricated as electrodes on titanium (Ti) and indium tin oxide (ITO) substrates and used as anode in electrochemical analysis. Complete decolorization was achieved with all the fabricated electrodes and higher rate of degradation was achieved with composite electrode (Ti/TiO2/Fe2O3) than individuals (bare Ti, Ti/TiO2, Ti/Fe2O3). Further, the same composite electrode shows better performance toward electrochemical water splitting in comparison with individual electrodes.