Unlocking the potential of chemical-assisted water electrolysis for green hydrogen production††

Despite global efforts to reduce the use of fossil fuels, carbon dioxide (CO₂) emissions continue to rise. As the demand for clean energy grows, hydrogen (H₂), which does not emit CO₂ during combustion, is emerging as a promising energy resource. Among the various hydrogen production technologies, water electrolysis is attracting attention as a method for producing green hydrogen without carbon emissions. However, its high reaction overpotentials, due to complex reaction pathways, are a major factor limiting its energy efficiency. To address these issues, chemical-assisted water electrolysis is considered as an innovative alternative. This technology enables hydrogen production at lower voltages. Moreover, it can generate high-value products and remove pollutants, providing both environmental and energy benefits. In this review, we introduce various types of chemical-assisted water electrolysis and discuss the latest advances in catalyst design and reaction mechanisms aimed at reducing applied system voltage. Finally, we address the main challenges and prospects of chemical-assisted water electrolysis.