H2 Production from Photocatalytic Assisted Electrolysis of Water

Electrolysis of water can be a promising way of producing green hydrogen gaseous because of its zero-carbon emission during the electrolysis process. For green hydrogen production, the electrical power source for electrolysis also should be supplied from a renewable source such as solar light, this is one of the reasons to increase the production cost of green hydrogen when compared to the production cost of grey hydrogen. Therefore it is important to increase electricity to hydrogen conversion efficiency. In this research, we utilized solar energy via WO₃ photocatalyst for water oxidation reaction and redox couple reduction. For efficient water oxidation and redox couple reduction, the noble-metal co-catalyst decorated WO₃ nanoparticle is designed. And then, the solar energy which is stored in the redox couple is subsequently used in the electrolysis process for hydrogen production reaction. This photolysis-electrolysis tandem system allows largely reduced operating voltage and also led to increased electrical power to hydrogen conversion efficiency.