Phys.org October 11, 2023 Using the Pt metal as the shell material of the catalyst in polymer electrolyte membrane fuel cells not only increases the surface area but also creates an interfacial interaction between the core metal and platinum, which results in enhanced catalytic activity. Researchers in Canada surface doped Pd@Pt nanoparticles with cobalt to further boost their durability and activity. Characterizing the synthesized catalyst with X-ray absorption fine structure at the Pt L3-edge and cobalt K-edges, together with performance tests, revealed information about the effect of the dopants on the catalytic activity of catalysts. The results of the local […]
Category Archives: Fuel cells
Efficient fuel-molecule sieving using graphene
Phys.org September 22, 2023 Proton exchange membranes with high proton conductivity and low crossover of fuel molecules are required to realize advanced fuel-cell technology. The selective transportation of protons, which occurs by blocking the transportation of fuel molecules across a proton exchange membrane, is crucial to suppress crossover while maintaining a high proton conductivity. An international team of researchers (Japan, Germany) proposed a simple yet powerful method for optimizing the crossover-conductivity relationship by pasting sulfanilic-functionalized holey graphenes onto a Nafion membrane. Their results showed that the sulfanilic-functionalized holey graphenes supported by the membrane suppressed the crossover by 89% in methanol […]
New ionic MOF materials boost hydrogen fuel cell efficiency
Nanowerk September 11, 2023 A few MOFs which typically use strong acids as proton sources, display superprotonic conductivity. However, they are rare due to the instability of MOFs in highly acidic conditions. Researchers in South Korea have shown superprotonic conductivity using a moderately acidic guest, zwitterionic sulfamic acid (HSA), which was encapsulated in MOF-808 and MIL-101. HSA acted not only as a proton source but also as a proton-conducting medium due to its extensive hydrogen bonding ability and zwitterion effect. A new sustained concentration gradient method resulted in higher HSA encapsulation compared to conventional methods. The MOFs showed impressive superprotonic […]
Researchers develop highly CO-tolerant fuel cell anode catalyst
Phys.org November 29, 2022 Platinum on carbon (Pt/C) catalyst is commercially adopted in fuel cells but it undergoes active-site poisoning by carbon monoxide (CO) diminishing the device performances. Researchers in China incorporated cobalt (Co) into molybdenum-nickel alloy (MoNi4), termed Co-MoNi4, which not only shows superior hydrogen oxidation reaction activity over the Pt/C catalyst in alkali, but exhibits excellent CO tolerance with only small activity decay after 10 000 cycles. It yielded peak power density far exceeding the Pt/C catalyst. Experimental and computational studies revealed that weakened CO chemisorption originates from the electron-deficient Ni sites… read more. TECHNICAL ARTICLE
Researchers develop world’s most durable hydrogen fuel cell
Nanowerk July 2, 2022 An international team of researchers (Hong Kong, USA – Argonne National Laboratory, China, Morocco) has designed a hybrid electrocatalyst that consists of atomically dispersed Pt and Fe single atoms and Pt–Fe alloy nanoparticles. Its Pt mass activity is 3.7 times higher than that of commercial Pt/C in a fuel cell. The fuel cell with a low Pt loading in the cathode shows an excellent durability, with a 97% activity retention after 100,000 cycles and no noticeable current drop at 0.6 V for over 200 hours. These results highlight the importance of the synergistic effects among active sites in […]
Carbon-coated nickel enables fuel cell free of precious metals
Science Daily March 24, 2022 An international team of researchers (USA – Cornell University, University of Madison, Japan, China) designed a nickel-based electrocatalyst with a 2-nanometer shell made of nitrogen-doped carbon. Their hydrogen fuel cell has an anode catalyst consisting of a solid nickel core surrounded by the carbon shell. When paired with a cobalt-manganese cathode, the resulting completely precious-metal-free hydrogen fuel cell outputs more than 200 milliwatts per square centimeter. The nickel oxide species on the surface of the nickel electrode slows the hydrogen oxidation reaction dramatically. The nitrogen-doped carbon coating serves as a protection layer and enhances the […]