A new nanocatalyst has been developed which converts the main greenhouse gases such as carbon dioxide (CO2) and methane (CH4) into gaseous hydrogen (H2) with high added value. This catalyst is expected to contribute greatly to the development of various waste-to-energy conversion technologies, as it has more than twice the conversion efficiency of CH4 to H2 compared to conventional electrode catalysts. The new development is reported by UNIST, Ulsan National Institute of Science and Technology in South Korea.
A team of researchers led by Professor Gun-Tae Kim from the School of Energy and Chemical Engineering at UNIST has developed a new method to improve the performance and stability of catalysts used in the reaction (e.g. dry methane reforming, DRM), which produces H2 and carbon monoxide (CO) from well-known greenhouse gases such as CO2 and CH4.
Conventional catalysts used for dry methane reforming are metal complexes based on nickel (Ni). However, over time, their characteristics deteriorate, and with them the life of the catalyst itself. This is due to the fact that carbon accumulates on the surface of catalysts.
“An even and quantifiable layer of iron (Fe) through atomic layer deposition (ALD) promotes topotactic decay by increasing finely dispersed nanoparticles,” explains Sangwuk Ju, PhD in the UNIST School of Energy and Chemical Engineering, the first author of the study.
The new catalyst has demonstrated high catalytic activity for the DRM process without noticeable degradation of performance over 410 hours of continuous operation. The results of the experiment also showed high methane conversion (over 70%) at 700 °C. “This is more than twice the energy conversion efficiency of conventional electrode catalysts,” said Professor Kim. “In general, the abundance of nanocatalysts from alloys obtained by atomic layer deposition marks an important step in the development of the decay process and its application in the field of energy use.