Tailoring metal/support interaction in 0D TiO2 NPs/MPs embedded 2D MAX composite with boosted interfacial charge carrier separation for stimulating photocatalytic H2 production

Abstract A novel fabrication of multilayered Ti3AlC2 MAX decorated with different sizes TiO2 to maximize charge carrier separation for stimulating photocatalytic H2 evolution has been investigated. Using TiO2 nanoparticles with ultrasonic approach, a good dispersion of TiO2 over 2D Ti3AlC2 nanosheets with proficient charge carrier separation was achieved. Highest H2 production rate of 9073 µmole g-1 h-1 was obtained over TiO2 NPs/Ti3AlC2 heterojunction, which is 10.9 and 26.4 folds higher than using pristine TiO2 and Ti3AlC2, respectively. This significantly enhanced activity was evidently due to faster charge transfer and separation over highly conductive Ti3AlC2 MAX structure. More importantly, when TiO2 MPs were loaded with Ti3AlC2, 9.3 folds lower H2 yield was attained compared to TiO2 NPs/Ti3AlC2 heterojunction synthesized through ultrasonic approach. This was apparently due to good interaction of TiO2 NPs with uniform distribution over 2D MAX multilayers to promote interfacial charge transfer. Glycerol, among the sacrificial reagents, gave highest H2 yield, whereas catalyst loading provides more active sites to boost photoactivity. This work provides a new pathway to use Ti3AlC2 MAX as an excellent co-catalyst with large interfacial contact and can be employed as an efficient structured material in energy application.