Core-Shell AgNWs@Ni(OH)2 Nanowires Anchored on Filter Paper for Efficient Hydrogen Evolution Reaction

Abstract

Transition metal (Fe, Ni, Co)-based hydroxides, especially nickel hydroxide (Ni(OH)2), have been considered as promising candidate for hydrogen evolution reaction (HER) because of their low cost, natural abundance and high catalytic performance. However, the catalytic performance of Ni(OH)2 is still unsatisfactory for practical application due to its relatively low electrical conductivity. Here, a highly conductive silver nanowires (AgNWs) network is prepared on filter paper, followed by the electrodeposition of Ni(OH)2 on the surface of AgNWs to form AgNWs@Ni(OH)2 core-shell structure. In comparison with pure Ni(OH)2 (376 mV at −10 mA cm−2), the optimized AgNWs@Ni(OH)2 electrode can exhibit about 3-fold enhanced HER performance, which achieves a lower overpotential of 123 mV at the current density of −10 mA cm−2, and a small Tafel slope of 76 mV dec−1 in 1 M KOH electrolyte. Besides the superior activity, the AgNWs@Ni(OH)2 electrode also shows a better durability. Such enhanced catalytic performance benefits from the high conductivity of AgNWs network to facilitate electron transfer, and the synergistic interaction between AgNWs and Ni(OH)2. This work also provides general strategies to design highly active HER electrocatalysts by utilizing highly conductive AgNWs to form core-shell architecture.