Electrocatalytic Hydrogen Production from Organic Molecule Oxidation

Electrocatalytic hydrogen production from organic molecule oxidation represents an emerging strategy to improve the energy efficiency and economic viability of water splitting. By replacing the energy-intensive oxygen evolution reaction at the anode with the oxidation of biomass-derived or small organic molecules, it is possible to reduce the overall cell voltage, generate value-added chemicals and simultaneously produce hydrogen at high purity. A broad palette of organic substrates has been explored, including alcohols, sugars, aldehydes and enols, under both alkaline and acidic conditions. Advances in catalyst design—ranging from transition-metal hydroxides and boride/metal heterostructures to noble-metal-modified electrodes—have yielded systems that deliver high current densities at low overpotentials, with Faradaic efficiencies approaching 100%. Mechanistic insight from operando spectroscopy and density functional theory has revealed key roles for electrophilic oxygen species, in situ-formed oxyhydroxides and synergistic metal–support interfaces. Such developments point towards the co-production of hydrogen and high-value chemicals, offering pathways to integrated biorefinery processes and more sustainable energy infrastructures.

Research from Nature Portfolio

Recent studies have elucidated a bifunctional mechanism for methanol-to-formate electro-oxidation on nickel-based hydroxides. In situ formation of NiIII-OOH and adjacent electrophilic oxygen species cooperatively catalyses both spontaneous and non-spontaneous methanol oxidation, achieving near-quantitative formate selectivity at low cell potentials and demonstrating superior activity of NiMn hydroxide over NiFe hydroxide.

Another advance utilised an acidic enol substrate, ascorbic acid, to achieve ampere-level hydrogen production at exceptionally low overpotentials. A single-atom iron catalyst stabilises the enol intermediate and drives anodic oxidation with only millivolt overpotentials, enabling a membrane-free electrolyser to reach industrial current densities with half the energy consumption of conventional water electrolysis.

A third work introduced a copper–silver electrocatalyst to replace oxygen evolution with partial formaldehyde oxidation. The Cu3Ag7 alloy stabilises a key hydrated intermediate, lowering the C–H cleavage barrier and allowing simultaneous hydrogen evolution at both electrodes. This system delivers an apparent Faradaic efficiency above 200% and a current density of 500 mA cm−2 at only 0.60 V cell voltage.

Electrocatalytic Hydrogen Production from Organic Molecule Oxidation publication trend

The graph below shows the total number of articles in electrocatalytic hydrogen production from organic molecule oxidation across all publications each year (not limited to Nature Index journals).

Technical terms

Electrocatalysis: The acceleration of an electrochemical reaction at an electrode surface by a catalyst.

Anodic oxidation: The electrochemical process in which a substrate loses electrons at the anode, often replacing oxygen evolution in hybrid electrolysis.

Faradaic efficiency: The proportion of electrical charge that contributes to the desired chemical transformation.

Overpotential: The additional potential required beyond the thermodynamic voltage to drive an electrochemical reaction at a given rate.

Oxyhydroxide: An in situ-formed species on transition-metal catalysts featuring mixed oxide and hydroxide character, often active in oxidation reactions.

Hybrid electrolysis: An approach combining hydrogen evolution at the cathode with oxidation of organic molecules at the anode to improve energy efficiency and generate valuable products.

References

1. Unraveling a bifunctional mechanism for methanol-to-formate electro-oxidation on nickel-based hydroxides. Nature Communications (2023).
2. Acidic enol electrooxidation-coupled hydrogen production with ampere-level current density. Nature Communications (2023).
3. Dual hydrogen production from electrocatalytic water reduction coupled with formaldehyde oxidation via a copper-silver electrocatalyst. Nature Communications (2023).
4. Vertical 3D Nanostructures Boost Efficient Hydrogen Production Coupled with Glycerol Oxidation Under Alkaline Conditions. Nano-Micro Letters (2023).
5. Coordination Effect-Promoted Durable Ni(OH)2 for Energy-Saving Hydrogen Evolution from Water/Methanol Co-Electrocatalysis. Nano-Micro Letters (2022).
6. Interfacial Electronic Modulation of Dual-Monodispersed Pt–Ni3S2 as Efficacious Bi-Functional Electrocatalysts for Concurrent H2 Evolution and Methanol Selective Oxidation. Nano-Micro Letters (2024).