Hydrogen is considered a promising energy vector, as its efficient use in fuel cells can strongly contribute to the reduction of air pollution. Therefore, the development of technology for sustainable hydrogen generation by the photocatalytic splitting of water is attracting worldwide an exponential growing attention. The photocatalytic formation of H2 and O2 on semiconductors, such as MTiO3 2 and MTaO2N3,4 , has been widely investigated due to the low band gap and high corrosion resistance of these semiconductor materials. However, the photocatalytic decomposition of water (H2O) is ineffective as the amount of hydrogen produced is limited by the rapid recombination of H2 and O2, resulting in the formation of water. More recently an alternative photocatalytic H2 production process has been proposed with consist of the addition of sacrificial methanol into water. In fact, methanol has a lower splitting energy than water. Most investigations of hydrogen production via methanol photodecomposition have focused on modifying TiO2 and noble metal (Cu, Ni, Pd, Pt, Au)-doped TiO2 , which can be used to activate the photocatalysts using UV light at longer wavelengths. However, their activity is still low.
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