Overall Water Splitting under Visible Light Irradiation Using Nanoparticulate RuO2 Loaded Cu2O Powder as Photocatalyst

Abstract

Overall decomposition of water into hydrogen and oxygen in presence of a heterogeneous photocatalyst has received prodigious attention due to its potential for the production of clean and recyclable hydrogen energy. However, most of the efficient photocatalysts developed till date, works primarily on ultra-violate range of light. To develop photocatalysts that can decompose water under more abundant visible range of light, efforts have already been made by researchers who basically tried to synthesize materials which have such a narrow band gap that they can utilize less energetic photons in visible range. To do so, the catalysts that they have prepared to exhibit high stability and to give decent reaction rate and quantum efficiency are of extremely complex structure. Moreover, cumbersome synthesis route involving doping of different materials, complicated core-shell nanostructure preparation, etc is necessary in most of the cases. Here, we report a facile and efficient approach to facilitate photocatalytic water-splitting under visible light, in single step. We have modified Cu2O, a well-known p-type semiconductor having a band-gap ∼2.1eV, with RuO2 nanoparticles and used it as photocatalyst. We have observed that it has a possibility of near-stoichiometric overall water decomposition under visible light with appreciable quantum efficiency.