Resolving optimal ionomer interaction in fuel cell electrodes via operando X-ray absorption spectroscopy.

To bridge the gap between oxygen reduction electrocatalysts development and their implementation in real proton exchange membrane fuel cell electrodes, an important aspect to be understood is the interaction between the carbon support, the active sites, and the proton conductive ionomer as it greatly affects the local transportations to the catalyst surface. Here we show that three Pt/C catalysts, synthesized using the polyol method with different carbon supports (low surface area Vulcan, high surface area Ketjenblack, and biomass-derived highly ordered mesoporous carbon), revealed significant variations in ionomer-catalyst interactions. The Pt/C catalysts supported on ordered mesoporous carbon derived from biomass showed the best performance under the gas diffusion electrode configuration.

Poly(ionic liquid) Ionomers Help Prevent Active Site Aggregation, in Single-Site Oxygen Reduction Catalysts.

Anion exchange membrane fuel cells (AEMFCs) can produce clean electricity without the need for platinum-group metals at the cathode. To improve their durability and performance, most research investigations so far have focused on optimizing the catalyst and anion exchange membrane, while few studies have been dedicated to the effect of the ionomer. Herein, we address this gap by developing a poly(ionic liquid)-based ionomer and studying its effect on oxygen transport and oxygen reduction kinetics, in comparison to the commercial proton exchange and anion exchange ionomers Nafion and Fumion.

Anion Exchange Ionomers: Design Considerations and Recent Advances - An Electrochemical Perspective.

Alkaline-based electrochemical devices, such as anion exchange membrane (AEM) fuel cells and electrolyzers, are receiving increasing attention. However, while the catalysts and membrane are methodically studied, the ionomer is largely overlooked. In fact, most of the studies in alkaline electrolytes are conducted using the commercial proton exchange ionomer Nafion.

Role of Ni in PtNi Bimetallic Electrocatalysts for Hydrogen and Value-Added Chemicals Coproduction via Glycerol Electrooxidation.

Pt-based bimetallic electrocatalysts are promising candidates to convert surplus glycerol from the biodiesel industry to value-added chemicals and coproduce hydrogen. It is expected that the nature and content of the elements in the bimetallic catalyst can not only affect the reaction kinetics but also influence the product selectivity, providing a way to increase the yield of the desired products. Hence, in this work, we investigate the electrochemical oxidation of glycerol on a series of PtNi nanoparticles with increasing Ni content using a combination of physicochemical structural analysis, electrochemical measurements, operando spectroscopic techniques, and advanced product characterizations.

Bioinspired and Bioderived Aqueous Electrocatalysis.

The development of efficient and sustainable electrochemical systems able to provide clean-energy fuels and chemicals is one of the main current challenges of materials science and engineering. Over the last decades, significant advances have been made in the development of robust electrocatalysts for different reactions, with fundamental insights from both computational and experimental work. Some of the most promising systems in the literature are based on expensive and scarce platinum-group metals; however, natural enzymes show the highest per-site catalytic activities, while their active sites are based exclusively on earth-abundant metals.