Electrolyte regulation in water electrolysis for hydrogen production

Hydrogen has received extensive attention due to its high energy density and non-polluting combustion products. How to prepare hydrogen energy in a clean and efficient way has become the research focus. Solar water splitting photovoltaic-electrolysis, photocatalysis, and photo-electrocatalysis for hydrogen generation by using naturally abundant solar energy and water are promising hydrogen production technologies. In the water splitting process, electrochemical reaction is the key step which directly determines the energy conversion efficiency of the whole system. However, most of the previous studies focused on the development of catalytic materials, while the influence of electrolyte characters on the electrolytic performance was usually neglected. Herein, the effects of electrolyte pH and ion composition on the surface catalytic reaction and mass transfer were firstly summarized according to the basic principles of water splitting. Then it was pointed out that improvement of energy conversion efficiency and stability in various water decomposition systems could be achieved by electrolyte regulation which showed influence on solid-liquid interfacial reaction. Finally, the future development direction of hydrogen production by water decomposition was proposed. © 2022, Editorial Office of FINE CHEMICALS. All right reserved.