Western University’s research team is constantly innovating to produce clean electricity. Fuel cells are the leading technology in this field and offer numerous advantages for the pursuit of sustainable solutions.
These devices are a promising path to clean energy, as they convert chemical energy into electricity efficiently with only heat and water as by-products. They are, therefore, an environmentally friendly choice for electricity production.
Polymer Electrolyte Membrane Fuel Cell (PEMFC) is one of the most promising fuel cell types due to its application in portable and stationary energy sources and transportation.
Platinum as a catalyst
The use and scarcity of platinum is a major obstacle to the adoption of PEMFCs. The reason for this dependency is that platinum facilitates the Oxygen Reduction Reaction (ORR). This is a key process within PEMFCs to produce electrical energy.
ORR is a complex series of reactions that reduce oxygen molecules to water. The fuel cells generate their electrical power through this process. Platinum acts as a catalyst, reducing the amount of energy needed to reduce oxygen molecules. The ORR would be too slow without platinum to produce practical and efficient electricity.
The high price and scarcity present significant challenges to the viability of PEMFCs. Platinum’s rising price has made its use in large-scale fuel cells economically prohibitive. This prevents PEMFCs from becoming mainstream clean energy solutions.
Platinum’s scarcity and high price make it difficult to use for large-scale fuel cells. (Shutterstock)
Our research focuses on developing catalysts that effectively replace platinum. Our team of researchers uses cutting-edge facilities such as the Canadian Light Source and the Advanced Photon Source.
We explore different strategies for developing catalysts and gain insights into their chemical and structural characteristics. This will help us to reduce our dependence on platinum.
The complex world of catalyst design
Our research focuses on catalyst design with particular attention to two fundamental techniques: alloying of platinum with transition metals and creating complex core-shell structures.
The process of alloying platinum involves mixing platinum with transition metals to improve catalytic performance. This results in catalysts that have increased reactivity and endurance. They are highly effective for a wide range of applications, including fuel cells.
Our research includes the development of complex coreshell structures. This approach involves a metallic core that is cost-effective and surrounded by shells made from another material. The covers provide protection and enhance catalytic performance.
This design provides precise control of catalytic reactions and surface properties, as well as the depreciation of material waste.
Persistent challenges
The durability of these catalyzers is a problem despite our advances. The inherent instability of these catalysts, which is their tendency to degrade lo effectiveness or undergo unwanted alterations, poses a significant roadblock to real-world applications.
Our team of researchers has discovered a possible solution: injecting cobalt-dopants in the surface and near-surface region of catalysts. The platinum-based spurs can withstand harsh conditions as well as the passage of time. This increases the durability and efficiency of these catalysts.
Our team created novel particles with a cobalt-doped, palladium-platinum shell and core. These particles have a unique octahedral shape and are extremely resistant to harsh chemical environments as well as prolonged use.
These nanoparticles are characterized by an innovative nanoscale structure that combines a palladium core with a platinum outer shell. The cobalt atom is added to the platinum shell. These nanoparticles are able to resist degradation and retain their catalytic properties for extended periods.
After 20,000 cycles of accelerated durability tests, which were designed to understand better how catalysts degrade under controlled laboratory conditions, the performance of these catalysts only decreased by two percent compared to the initial state of the test.
Future
Core-shell nanoparticles could revolutionize fuel cell technology with a palladium and platinum core doped with cobalt. They promise to be highly efficient ORR catalysts that will last for a long time. This could lead us towards a sustainable energy future.
Our research is in line with the urgent necessity to combat global climate change. We can create a sustainable future by replacing fossil fuels and other energy sources with cleaner alternatives.
