Boosting electrocatalytic oxygen evolution activity by in-situ growth of hierarchical vertically-erected Ni(OH)2 nanosheets on Ag nanowires

A core-shell hierarchical nanoarchitecture consisting of Ni-layered double hydroxide nanosheets (Ni(OH)2 NSs) grafted on Ag nanowires (Ag NWs) backbone is rationally designed and built by an in situ growth route, in which Ag NWs act as core and Ni(OH)2 NSs as shell. The resulting hybrid material (Ag NW@Ni(OH)2 NS), displayed a three-dimensional structure with a well-defined core-shell configuration and enlarged surface area, exhibits excellent electrocatalytic performance and enhanced durability. An electrochemical analysis exhibits that the Ag NW@Ni(OH)2 NS-2H catalyst is a low overpotential of 290 mV required the achievement of a current density at 10 mA cm-2 (j10) and excellent long-term stability sustained over 24 h with only 6% potential increment at j10 versus initial potential. Unique micro/macrostructure and synergistic effects are responsible for the extraordinary electrochemical performance of Ag NW@Ni(OH)2 NS-2H core-shell composite. Ag NWs behave like a high conductive backbone due to their low intrinsic resistance, thus promoting charge transfer, whereas the hierarchical Ni(OH)2 nanosheets, with huge surface area, provide a large number of active sites for oxygen evolution reaction, leading to (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this study, a core-shell hierarchical nanoarchitecture consisting of Ni-layered double hydroxide nanosheets grafted on Ag nanowires backbone was designed and built by an in situ growth route. The resulting hybrid material exhibited excellent electrocatalytic performance and enhanced durability, attributed to its unique micro/macrostructure and synergistic effects.