The global push for clean hydrogen production is gaining momentum, driven by the urgent need to tackle climate change and environmental pollution. Water electrolysis, a technology that produces hydrogen without carbon dioxide (CO2) emissions, is at the forefront of this movement. However, the technology faces significant hurdles, particularly the challenge of reduced energy efficiency due to high operating voltage. As the world grapples with rising CO2 emissions—expected to hit 37.4 billion tonnes in 2024, a 0.8% increase from the previous year—innovations in hydrogen production are more critical than ever.
The imperative to reduce fossil fuel consumption and develop alternative clean energy technologies is clear. Hydrogen, with its high energy density and zero CO2 emissions during combustion, is emerging as a viable solution. It plays a pivotal role in addressing the intermittency of renewable energy sources like solar and wind. By converting excess electricity into hydrogen, this element offers a robust solution for energy storage and transportation. To fully harness this potential, producing hydrogen without carbon emissions is essential.
Chemical water electrolysis is stepping into the spotlight as a promising solution. This technology produces hydrogen at a lower voltage by substituting the water oxidation reaction (OER) with various chemical oxidation reactions, such as ammonia, alcohol, urea, and hydrazine. It also holds the potential to enhance energy production and promote environmental improvement by generating high-value products or eliminating pollutants.
A team of researchers, led by Ho Won Jang from Seoul National University, has introduced various chemical water electrolysis systems and systematically analyzed the latest catalyst design strategies to tackle the high overpotential issues of each reaction. “Chemical water-assisted electrolysis technology represents an innovative approach to overcoming the limitations of conventional water electrolysis, enabling clean hydrogen production with enhanced energy efficiency,” Jang explained. This study aims to provide a comprehensive blueprint for industrial applications, outlining the latest research trends and catalyst design strategies.
However, chemical water electrolysis faces technical challenges that must be overcome before it can replace conventional electrolysis methods. Key issues include maintaining catalyst durability and achieving low-voltage operation. Researchers are actively addressing these through electrochemical reaction mechanism studies and AI-driven catalyst design. For industrial applications, achieving high current density and long-term stability is crucial. Recent developments in membrane electrode assembly (MEA) and fuel cell-type devices operating under high-temperature conditions are promising steps forward. Additionally, efforts to develop self-powered hydrogen production systems are underway.
As these advancements progress, chemical water electrolysis could become a cornerstone in the transition to sustainable, clean energy solutions. The technology’s potential to enhance energy efficiency and reduce environmental impact makes it a vital area of focus for researchers and industry stakeholders alike. The systematic compilation of the latest catalyst design strategies and their potential for improving energy efficiency is a significant step toward industrial applications. The future of green hydrogen production through electrolysis looks promising, with ongoing research and development paving the way for a cleaner, more sustainable energy landscape.
