Photo-Enhanced Electrocatalysis in Zinc-Air Batteries

Photo-enhanced electrocatalysis in zinc–air batteries integrates light absorption with catalytic oxygen reactions to reduce charging overpotentials and boost overall energy efficiency. In these systems, a semiconductor photoelectrode or photoactive catalyst layer absorbs solar radiation to generate photogenerated charge carriers, which drive the oxygen evolution reaction (OER) during charging or enhance the oxygen reduction reaction (ORR) during discharge. By tailoring band structures, heterojunction interfaces and catalyst compositions, researchers have achieved significant reductions in charge–discharge voltage gaps, improvements in round-trip efficiency and extended cycling stability. This approach holds global appeal for grid-scale storage and portable applications, as it couples abundant solar energy with a low-cost, high-energy-density metal–air chemistry, thereby advancing sustainable energy storage and carbon-neutral technologies.

Research from Nature Portfolio

Recent studies have demonstrated the feasibility and underlying design principles of photo-assisted zinc–air systems. Early foundational work introduced sunlight-promoted zinc–air cells employing BiVO₄ or α-Fe₂O₃ photoelectrodes, achieving charge potentials as low as 1.20 V under illumination—0.5–0.8 V below conventional values—by optimising band alignment and photoelectrode stability. Building on this, interfacial engineering strategies have delivered semiconductor–electrocatalyst nanoarchitectures, such as CdS/CdSe–MoS₂ combined with NiFe layered double hydroxides, which record low overpotentials for oxygen evolution under illumination and maintain high photocurrents over extended operation. These insights into light-driven charge separation and catalyst activation now guide the development of integrated photo-electrochemical zinc–air devices.

Photo-Enhanced Electrocatalysis in Zinc-Air Batteries publication trend

The graph below shows the total number of articles in photo-enhanced electrocatalysis in zinc-air batteries across all publications each year (not limited to Nature Index journals).

Technical terms

Photoelectrocatalysis: enhancement of electrochemical reaction rates by combining a light-absorbing semiconductor with a catalytic surface to generate and utilise photogenerated charge carriers.

Zn–air battery: a metal–air electrochemical cell in which zinc is oxidised at the anode and oxygen is reduced at the cathode, producing electrical energy.

Overpotential: the extra potential beyond the thermodynamic voltage required to drive an electrochemical reaction at a desired rate.

Oxygen evolution reaction (OER): the anodic half-reaction in which water or hydroxide ions are oxidised to release molecular oxygen during charging.

Photoelectrode: a semiconductor electrode that absorbs photons to generate a photovoltage or photocurrent, thereby driving electrochemical processes.

References

1. Utilizing solar energy to improve the oxygen evolution reaction kinetics in zinc–air battery. Nature Communications (2019).
2. A semiconductor-electrocatalyst nano interface constructed for successive photoelectrochemical water oxidation. Nature Communications (2023).
3. Ultralow charge–discharge voltage gap of 0.05 V in sunlight‐responsive neutral aqueous Zn–air battery. Carbon Energy (2024).
4. Photo-Charging a Zinc-Air Battery Using a Nb2O5-CdS Photoelectrode. Catalysts (2022).
5. Engineering the next generation of photorechargeable zinc-air batteries. Current Opinion in Electrochemistry (2022).