Electrocatalytic performance in direct ethanol fuel cells: Contributions of monometallic, bimetallic, and trimetallic catalysts

Over the recent past, there has been exponential growth in the advancements of clean energy sources and fuel cell technologies. Fuel cells are the electrochemical devices that are able to convert chemical energy of a fuel into electrical energy. This paper studies the electrocatalytic activity of monometallic, bimetallic, and trimetallic catalysts in direct ethanol fuel cells (DEFCs). Monometallic catalysts, for example, platinum (Pt) and palladium (Pd), along with other transition metals, find application but have complications like poor tolerance to carbon monoxide (CO) and incomplete oxidation of ethanol. Furthermore, bimetallic catalysts, e.g., Pt-Ru and Pt-Sn, have shown significant advancements because of these synergistic enhancements, leading to improved performance, stability, and CO poisoning resistance. Another group of catalysts, trimetallic (e.g., Pt-Ru-Sn), have both high efficiency and long-lasting capabilities, making them stand out as applicable in most DEFC practical scenarios. This research proves the advantage of multi-metallic catalysts in developing the DEFC technology while solving both major factors of catalyst deterioration and their price.