Formation of 1D Hierarchical Structures Composed of Ni3S2 Nanosheets on CNTs Backbone for Supercapacitors and Photocatalytic H2 Production

One‐dimensional (1D) hierarchical structures composed of Ni3S2 nanosheets grown on carbon nanotube (CNT) backbone (denoted as CNT@Ni3S2) are fabricated by a rational multi‐step transformation route. The first step involves coating the CNT backbone with a layer of silica to form CNT@SiO2, which serves as the substrate for the growth of nickel silicate (NiSilicate) nanosheets in the second step to form CNT@SiO2@NiSilicate core‐double shell 1D structures. Finally the as‐formed CNT@SiO2@NiSilicate 1D structures are converted into CNT‐supported Ni3S2 nanosheets via hydrothermal treatment in the presence of Na2S. Simultaneously the intermediate silica layer is eliminated during the hydrothermal treatment, leading to the formation of CNT@Ni3S2 nanostructures. Because of the unique hybrid nano‐architecture, the as‐prepared 1D hierarchical structure is shown to exhibit excellent performance in both supercapacitors and photocatalytic H2 production. Coaxial CNT‐supported Ni3S2 ultrathin nanosheets fabricated via a multi‐step conversion route exhibit interesting properties as electrode materials for supercapacitors and as a photocatalyst for hydrogen production from water splitting.