Search

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Developing low‐cost and high‐activity pH‐universal hydrogen evolution reaction (HER) catalysts is very crucial to the industrialization of water electrolysis. However, the high price, low yield, and poor stability of current HER catalysts make them difficult to meet practical requirements. Herein, a plasma spraying technique is employed to prepare self‐supported Cu catalysts with tensile strain for the first time. The tensile strain upshifts the d‐band of Cu, improves the water dissociation and H* adsorption, eventually improves the intrinsic HER catalytic activity. As such, Cu electrode achieves overpotentials of 182 mV in 0.5 m H2SO4, 261 mV in 1 M PBS, and 121 mV in 1 M KOH at 10 mA cm–2. In addition, Cu electrode also performs well at high current densities, the overpotentials at 1 A cm–2 are much lower than those of Pt foil in acid, neutral, and alkaline solutions. [ABSTRACT FROM AUTHOR]

A self-supported silver electrode was prepared by plasma spraying and used for catalysing the hydrogen evolution reaction. Thanks to the non-equilibrium synthetic conditions, the silver catalyst exposes high-energy (200) crystal planes, which enhance the adsorption of hydrogen and improve the intrinsic catalytic activity. As a result, the silver catalyst delivers an overpotential of 349 mV at 10 mA cm−2, which was much lower than those of Ag foil (742 mV) and commercial Ag powder (657 mV). This work provides a new idea of preparing active electrocatalysts by traditional processes. [ABSTRACT FROM AUTHOR]

As a cheap and earth-abundant metal, copper is known highly conductive but inactive for catalyzing hydrogen evolution reaction (HER) due to its fully filled d orbital and weak adsorption for hydrogen intermediate. Herein, we adopt a mechanical stirring process to introduce a large number of dislocations into copper plate, and retain the dislocations by the quenching effect of dry ice. Theoretical computation indicates that dislocation can cause uneven distribution of charge density, and the electron-deficient area remarkably enhances the hydrogen adsorption, turning inactive copper into active HER catalyst. The product achieves high turnover frequency, low overpotential and long-term durability. Our work bridges mechanical process and functional materials, and exploits a powerful technology on producing self-supported catalysts in a rapid way : [Display omitted] [ABSTRACT FROM AUTHOR]