Enhanced photocatalytic hydrogen production from Y2O3/TiO2 nano-composites: a comparative study on hydrothermal synthesis with and without an ionic liquid

Hetero-junction Y2O3/TiO2 nano-composite (NC) photocatalysts were synthesized using a conventional hydrothermal method (Y2O3/TiO2 NC(HM)) and an ionic liquid assisted hydrothermal method (Y2O3/TiO2 NC(ILAHM)). The composite nature and physico-chemical properties of the photocatalysts prepared through both routes as a function of thermal treatment were investigated via thorough characterization. A comparison of the photocatalytic hydrogen production via water splitting is provided. It was found that the concentration of Y2O3 in the TiO2 matrix and the post thermal treatment have obvious effects on the hydrogen production activity, and they were fine-tuned for enhancement of the hydrogen production. The required synergy between Y2O3 and TiO2 was found to occur at an optimum concentration of 25 wt% Y2O3 in the TiO2 matrix, with the sample prepared at 400 degrees C for 1 h. The optimized NC i.e. 25 wt% Y2O3/TiO2 NC(ILAHM) produced a promising hydrogen evolution of 1380 mu mol g(-1) that was almost 2-fold the production from 25 wt% Y2O3/TiO2 NC(HM). The enhancement was attributed to the porous surface morphology, higher surface area and quantum yield of the NC prepared using the ionic liquid assisted hydrothermal method.