Cost-effective electrocatalysts for cleaner hydrogen fuel production

Cost-effective electrocatalysts for cleaner hydrogen fuel production
by Simon Mansfield
Sydney, Australia (SPX) Dec 04, 2023

In an era increasingly defined by the urgent need to shift away from carbon-based energy sources, a team of researchers has made significant strides in the field of low or no-carbon alternatives. In a study published in Nano Research Energy on November 22, 2023, scientists from Jilin University unveiled a novel method for producing hydrogen - a promising and clean energy source - through the process of water splitting, using non-precious metal electrocatalysts.

The study's focus is on transition metal sulfides, specifically tin (Sn), cobalt (Co), and iron (Fe), deployed on nickel foam to develop cost-effective and environmentally friendly catalysts. This approach represents a significant departure from traditional methods that often rely on expensive and less sustainable precious metals.

Central to this research is the material FeSnCo0.2SxOy/NF, which has shown potential as both an anode and cathode in the water-splitting process. The process comprises two key reactions: oxygen evolution reactions (OER), which produce O2 from water, and hydrogen evolution reactions (HER), yielding hydrogen fuel through a two-electron transfer reaction. The team's work focuses on enhancing the stability and efficiency of these reactions, particularly in terms of continuous use and overpotential requirements.

The hydrogen evolution reaction (HER) has demonstrated notable stability, maintaining effectiveness for up to 55 hours of continuous operation, and requiring a lower overpotential than the oxygen evolution reaction. However, the oxygen evolution reaction presents more challenges, with stability concerns arising from the complex electron transfer steps and harsh electrolytic conditions. Despite these challenges, the research team notes improvements in OER stability and activity when using the combination of iron, tin, and cobalt on nickel foam.

Jingqi Guan, one of the study's authors, emphasized the importance of this research in the context of renewable energy, stating, "It is pivotal to improve the OER stability of transition metal sulfides, so that they can be used as bifunctional HER and OER catalysts for reversible hydrogen fuel cells."

The team's approach also involves the use of heterostructural interfaces, referring to a semiconductor structure that can vary in chemical composition. This variation in the sulfide/oxyhydroxide duo allows for an even distribution of electrons across the electrolyte surface, promoting effective charge transfer and enhancing the overall activity and stability of the system.

The synergistic effect of these transition metals, particularly in hydrogen evolution reactions, underscores their potential in addressing the challenge of reducing reliance on carbon-based energy sources. The results, though promising, also highlight areas for future improvement. Minimizing overpotentials to reduce the energy input required for the reactions, and ensuring the durability of these electrocatalysts for commercial use, remain critical goals for the long-term success of this technology.

Contributing to this groundbreaking research were Siyu Chen, Ting Zhang, Jingyi Han, Shihui Jiao, and Jingqi Guan from the Institute of Physical Chemistry at Jilin University, Hui Qi from the Second Hospital of Jilin University, and Changmin Hou from the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry at Jilin University. Their collective work represents a meaningful step forward in the global effort to develop cleaner, more sustainable energy solutions.

Research Report:Interface engineering of Fe-Sn-Co sulfide/oxyhydroxide heterostructural electrocatalyst for synergistic water splitting