Water Electrolysis Breakthrough: Swapping Waste Oxygen for Formic Acid

95% formic acid Faraday efficiency. This figure represents a significant leap in value capture for electrochemical systems. Traditional water electrolysis is currently hamstrung by the oxygen evolution reaction (OER). OER is energy-hungry. It is kinetically sluggish. Worst of all, it produces oxygen, a byproduct with negligible economic value compared to the energy required to generate it. This study introduces an innovative sequential strategy to bypass this limitation entirely.

Redefining Water Electrolysis Chemistry

The research team successfully replaced the inefficient OER with methanol oxidation (MOR). This is not merely a chemical substitution; it is an economic restructuring of the reaction process. The method decouples the cathodic hydrogen evolution reaction (HER) from the anodic reaction. In the first stage, Ni(OH)₂ is oxidised to NiOOH within a 1 M KOH electrolyte. This step effectively charges the catalyst while hydrogen is produced. Subsequently, the process shifts. In a neutral electrolyte, the NiOOH spontaneously reduces via MOR. This reaction selectively generates formic acid (HCOOH), a high-value industrial chemical.

Scalability and Measured Outcomes

The team utilised a scalable bottom-up method to prepare the active NiOOH catalyst directly from particles. The measured yield reached 48.25 mmol of HCOOH per kg of catalyst. This data indicates that the active sites are highly accessible. The use of neutral media for the product generation step is significant. It mitigates corrosion issues often associated with harsh alkaline environments used in standard electrolysis. While the laboratory results confirm high selectivity and chemical feasibility, the data suggests that this strategy could offer a recyclable pathway for industrial application. By transforming the anode reaction from a cost centre into a profit generator, the economics of green hydrogen become far more attractive.