The low-cost hydrogen production from water electrolysis is crucial to the deployment of sustainable hydrogen economy but is currently constrained by the lack of active and robust electrocatalysts from earth-abundant materials. We describe here an unconventional heterostructure composed of strongly coupled Ni-deficient LiNiO nanoclusters and polycrystalline Ni nanocrystals and its exceptional activities toward the hydrogen evolution reaction (HER) in aqueous electrolytes. The presence of lattice oxygen species with strong Brønsted basicity is a significant feature in such heterostructure, which spontaneously split water molecules for accelerated Volmer H-OH dissociation in neutral and alkaline HER. In combination with the intimate LiNiO and Ni interfacial junctions that generate localized hotspots for promoted hydride coupling and hydrogen desorption, the catalysts produce hydrogen at a current density of 10 mA cm under overpotentials of only 20, 50, and 36 mV in acidic, neutral, and alkaline electrolytes, respectively, making them among the most active Pt-free catalysts developed thus far. In addition, such heterostructures also exhibited superior activity toward the hydrogen oxidation reaction in alkaline electrolytes.
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http://dx.doi.org/10.1021/jacs.0c00241 | DOI Listing |
Nanoscale Horiz
January 2025
Research & Development Institute of Northwestern Polytechnical University in Shenzhen, Shenzhen, 518057, China.
Over-oxidation of surface ruthenium active sites of RuO-based electrocatalysts leads to the formation of soluble high-valent Ru species and subsequent structural collapse of electrocatalysts, which results in their low stability for the acidic oxygen evolution reaction (OER). Herein, a binary RuO/NbO electrocatalyst with abundant and intimate interfaces has been rationally designed and synthesized to enhance its OER activity in acidic electrolyte, delivering a low overpotential of 179 mV at 10 mA cm, a small Tafel slope of 73 mV dec, and a stabilized catalytic durability over a period of 750 h. Extensive experiments have demonstrated that the spillover of active oxygen intermediates from RuO to NbO and the subsequent participation of lattice oxygen of NbO instead of RuO for the acidic OER suppressed the over-oxidation of surface ruthenium species and thereby improved the catalytic stability of the binary electrocatalysts.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Electronic Science and Technology of China, State Key Laboratory of Electronic Thin Films and Integrated Devices, No. 2006, Xiyuan Avenue, High-tech Zone (West Area), 610054, Chengdu, CHINA.
Bismuth oxide (Bi2O3) emerges as a potent catalyst for converting CO2 to formic acid (HCOOH), leveraging its abundant lattice oxygen and the high activity of its Bi-O bonds. Yet, its durability is usually impeded by the loss of lattice oxygen causing structure alteration and destabilized active bonds. Herein, we report an innovative approach via the interstitial incorporation of indium (In) into the Bi2O3, significantly enhancing bond stability and preserving lattice oxygen.
View Article and Find Full Text PDFExtracorporeal Membrane Oxygenation (ECMO) serves as a crucial intervention for patients with severe pulmonary dysfunction by facilitating oxygenation and carbon dioxide removal. While traditional ECMO systems are effective, their large priming volumes and significant blood-contacting surface areas can lead to complications, particularly in neonates and pediatric patients. Microfluidic ECMO systems offer a promising alternative by miniaturizing the ECMO technology, reducing blood volume requirements, and minimizing device surface area to improve safety and efficiency.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, P. R. China.
Designing catalysts with both activity and stability remains a grand challenge for the removal of chlorinated volatile organic compounds (CVOCs) by catalytic oxidation. Herein, the Ru-Mn subnanometric species encapsulated in ZSM-5 zeolite (RuMn@Z) was synthesized. It shows that the 90% conversion of dichloromethane is as low as 320 °C, which is significantly lower than that of Ru@Z (350 °C) and the impregnation catalyst (RuMn/Z, 355 °C).
View Article and Find Full Text PDFSensors (Basel)
January 2025
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
This study has investigated the effects of different annealing temperatures on the microstructure, chemical composition, phase structure, and piezoelectric properties of ZnO films. The analysis focuses on how annealing temperature influences the oxygen content and the preferred c-axis (002) orientation of the films. It was found that annealing significantly increases the grain size and optimizes the columnar crystal structure, though excessive high-temperature annealing leads to structural degradation.
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