A groundbreaking technology has been developed to address the limitations of current catalyst electrodes, facilitating the large-scale production of green hydrogen at a relatively low cost. This significant advancement was published in the Journal of the American Chemical Society.
The innovative project was led by Professor Han Gi Chae from the Department of Materials Science and Engineering and Professor Jong-Beom Baek from the School of Energy and Chemical Engineering at UNIST, in collaboration with Professor Kafer T. Tavuz at King Abdullah University of Science and Technology (KAUST). Together, they have developed carbon fabric electrocatalysts embedded with highly functional catalysts, utilizing a conventional carbon fiber/fabric manufacturing process.
This cutting-edge design ensures stable operation across extensive areas by employing a carbon fiber catalyst instead of the conventional powder-type catalyst, which is prone to detachment. Remarkably, the new electrode boasts a lifespan 100 times longer than traditional electrodes while maintaining optimal performance. By using ruthenium instead of the more expensive platinum, the researchers have significantly reduced manufacturing costs.
Historically, electrochemical electrodes were created by spraying a powder catalyst, such as carbon powder, onto the electrode for fixation. This method often resulted in uneven application, leading to issues like clumping or detachment of the powder. In contrast, carbon fiber-based electrochemical electrodes are attracting attention for their high thermal and electrical conductivity properties, as well as their adaptability across large surfaces.
Advancing this concept, the research team integrated ruthenium (Ru) into the polymer precursor fiber during the manufacturing process, thereby enhancing the catalyst's stability. By utilizing polyacrylonitrile (PAN) as the precursor polymer, they effectively stabilized the catalyst's characteristics. Additionally, ruthenium was selectively affixed to the surface as a chemical catalyst, replacing platinum.
The team's ruthenium surface–embedded fabric electrocatalysts (Ru–SFECs) exhibited a low overvoltage of 11.9 mV at a current density of 10 mA cm–2, indicating low energy consumption during the hydrogen generation process. Notably, the developed electrode demonstrated a minimal overvoltage increase of just 6.5% after 10,000 operations, a substantial improvement over commercialized platinum powder catalysts.
The newly designed carbon fiber electrode with a functional catalyst presents a significant cost advantage over traditional electrodes reliant on expensive platinum-based catalysts. By utilizing ruthenium instead of platinum and incorporating it into the polymer precursor fiber early in the manufacturing process, the researchers were able to create Ru–SFECs with a low overpotential of 11.9 mV at a current density of 10 mA cm–2, showcasing remarkable stability and efficiency.
This innovative approach harnesses the exceptional mechanical and electrical properties of carbon fibers, demonstrating their potential as a versatile material for future electrochemical reactions. Through meticulous control of catalyst metal separation and microcarbon structure, the team achieved maximum stability and activity, enabling the continuous production of catalyst fibers for direct industrial applications.
The development of these advanced carbon fiber electrocatalysts marks a significant milestone in the quest for efficient and affordable green hydrogen production. By overcoming the limitations of traditional catalyst electrodes, this technology holds great promise for scaling up green hydrogen production, thereby contributing to a more sustainable and energy-efficient future.
Source: Ulsan National Institute of Science and Technology