Prof. NI Meng conducts research on zinc-air seawater batteries and publishes findings in Nano Materials Science | PolyU Academy for Interdisciplinary Research (PAIR)

Prof. NI Meng, Associate Dean of Faculty of Construction and Environment, Head of Department of Building Environment and Energy Engineering and Chair Professor of Energy Science and Technology of PolyU, in collaboration with the State Key Laboratory of Rare Earth Resource Utilization and City University of Hong Kong, has conducted a study on zinc-air seawater batteries and recently published a paper titled “Turning seawater chloride ion from corrosion agent to OER accelerator and stabiliser via oxygen vacancy engineering and application in zinc-air seawater batteries” in Nano Materials Science.

Zinc–air seawater batteries (ZASBs) represent a promising technology due to their high energy density, environmentally friendly nature, and low cost. However, their performance is hindered by the slow oxygen evolution reaction (OER) and rapid deactivation of OER electrocatalysts caused by chloride ion (Cl⁻) corrosion. The research team has proposed an innovative oxygen vacancy (O_v) strategy that not only mitigates Cl⁻ corrosion but also utilises Cl⁻ as an OER accelerator and catalyst protector. Specifically, oxygen vacancies are introduced into NiFe₂O₄ via in situ growth on self-supported carbon substrates. These vacancies enhance Cl⁻ adsorption, forming Cl⁻-O_V-NiFe₂O₄ catalyst. This synergistic interaction enables superior OER activity, achieving a low overpotential of 285 mV at 100 mA cm⁻² in alkaline seawater, whereas pristine NiFe2O4 is unable to reach this current density threshold.

The enhanced ZASB achieves a lifespan exceeding 400 cycles, which is 45 times greater than that of pristine NiFe2O4 (9 cycles). The proposed oxygen vacancy strategy not only advances the practical application of ZASBs, but also provides valuable insights for the development of seawater battery technologies.

Prof. NI Meng is currently Management Committee Member of Otto Poon Charitable Foundation Research Institute for Smart Energy (RISE), Member of Research Institute for Sustainable Urban Development (RISUD).

Read the full paper: https://www.sciencedirect.com/science/article/pii/S2589965125000820?via%3Dihub