Hydrogen-oxygen (H2/O2) fuel cells offer a promising clean energy solution by converting the chemical energy from hydrogen and oxygen into electricity, with water as only the byproduct. This review outlines the principles behind H2/O2 fuel cells, including electrochemical reactions, thermodynamic considerations and the role of advanced materials like catalysts, membranes and electrodes. It addresses key challenges such as catalyst degradation, water management and hydrogen storage, alongside strategies to overcome these issues, including non-precious metal catalysts, high-temperature proton-exchange membranes and optimized cell designs. The diverse applications of H2/O2 fuel cells, spanning transportation, stationary power generation and portable devices, highlight their potential to decarbonize various industries. The importance of green hydrogen production from renewable energy sources was emphasized and the need for infrastructure to support large-scale fuel cell deployment. As fuel cell technology advances, the transition to a hydrogen economy provides a pathway to achieving net-zero carbon emissions. Continued interdisciplinary research and development are crucial to overcoming existing barriers, enhancing scalability and ensuring the widespread adoption of H2/O2 fuel cells as a key component of sustainable energy systems.
Rajapakse et al. (2025) studied this question.