Fundamental insight into enhanced activity of Pd/CeO₂thin films in hydrogen oxidation reaction in alkaline media

Abstract

In situ electrochemical quartz crystal microbalance (E-QCM) provides new insight into enhanced activity of palladium supported on ceria (Pd/CeO2) in hydrogen oxidation reaction.

PtIrFeCoNiMo high-entropy alloy nanodendrites for boosting the alkaline hydrogen oxidation performance

“…3c displays the plots of j k vs. overpotentials obtained by Butler–Volmer fitting. 16,47 As listed in Table S2,† the j k normalized by the mass of metal ( j k,m ) at the overpotential of 50 mV for HEA NDs/C (3.53 mA g PGM −1 ) is about 1.7 and 14 times higher than those for HEA NPs/C (2.07 mA g PGM −1 ) and Pt/C (0.25 mA g PGM −1 ), respectively. This indicates the significantly enhanced HOR kinetics on HEA NDs/C.…”

“…12,13 Therefore, the hydrogen binding energy (HBE) and hydroxyl binding energy (OHBE) have been verified to be vital descriptors for assessing the current alkaline HOR. 14–16 As for Pt, though it is often used as a benchmark for comparing the HOR performance, it still has a relatively strong HBE. 13,17 Especially, the OHBE on the surface of Pt is too weak, resulting in a high energy barrier of the Volmer step.…”

Antibacterial and anti-inflammatory polyethyleneimine/polyacrylic acid hydrogel loaded with CeO2 quantum dots for wet tissue wound dressings

“…The loss of oxygen atoms from the lattice can result in oxygen vacancy due to the reduction in Ce 4+ . A higher Ce 3+ ratio, or more oxygen vacancies, has been demonstrated to correspond to SOD enzyme mimic activity (Li et al, 2023;Luneau et al, 2023), while a lower Ce 3+ ratio implies a higher CAT mimic activity (Chen and Stephen Inbaraj, 2018;Yadav et al, 2022). Tiny particle-sized CeO 2 -QDs have an increased fraction of Ce 3+ than large particle-sized CeO 2 nanoparticles due to the size effect, implying that CeO 2 -QDs exhibit an enhanced antibacterial effect (Xue et al, 2011;Kilic et al, 2021).…”

“…CeO 2 nanoparticles were frequently used in self-regenerating antioxidative and anti-inflammatory medicines for a variety of disorders based on their capacity to scavenge ROS (Kim et al, 2023;Meng et al, 2024;Yang et al, 2024). The tuning of particle size was reported to play an important role in determining the physical, chemical, and biological properties of CeO 2 (Hosseini and Mozafari, 2020;Luneau et al, 2023). Particularly, CeO 2 quantum dots (QDs) have drawn significant attention according to the size effect, which guaranteed enhanced surface exposure and profound structure modulation (Younis et al, 2013;Kong et al, 2018;Kar et al, 2022).…”

Hydrogen oxidation electrocatalysts for anion-exchange membrane fuel cells: activity descriptors, stability regulation, and perspectives

“…A pivotal aspect of rational heterointerface design is the maximization of synergistic effects, thereby benefiting the fundamental steps in the HOR. 89 Noteworthy efforts have been directed towards leveraging interfacial interactions to optimize the HBE or OHBE in various heterostructures, including Ni/Ni 3 N, 139,293 Co/Co 2 N, 294 Ni/NiO, 121,122 Ni–V 2 O 3 , 295 Ni–MoO 2 , 296 Ni/N 3 B, 278 Ni/Ni 3 C, 202 Ni 3 N–Ni(OH) 2 , 284 Ni/BN, 297 Pd/CeO 2 , 298–300 Ir/WO x , 187 PtNi 2 /carbon dots, 233 RuO 2 –PdO nanowires, 301 Ru/Ni 3 N, 302 and others. An illustrative example of effective interface engineering is demonstrated by Dario et al , who modified CeO 2 on the surface of Pd NPs, resulting in the fabrication of the Pd–CeO 2 /C catalyst.…”