Amorphous Ni(OH)2 encounter with crystalline CuS in hollow spheres: A mesoporous nano-shelled heterostructure for hydrogen evolution electrocatalysis

Highly active, durable and cost-effective eletrocatalysts are crucial for hydrogen evolution reaction (HER). Herein, we report novel hollow hybrid spheres comprising of amorphous Ni(OH) 2 and crystalline CuS mesoporous nano-shelled heterostructures as efficient HER electrocatalysts . Spherical Cu 2 O particles are used as templates for fabrication of Ni(OH) 2 @CuS hollow spheres with nano-shelled heterostructures . The as-obtained catalysts exhibit much higher performance than the single Ni(OH) 2 , CuS, their physical mixture and crystalline Ni(OH) 2 @CuS toward water electrochemical reduction in alkaline medium . The superior HER electrocatalytic performance might be attributed to the unique hollow mesoporous nanoshelled architecture and the heterostructured synergetic effects between amorphous Ni(OH) 2 and crystalline CuS, in which the short-range order of the inner amorphous Ni(OH) 2 mesoporous shell creates abundant active sites on the surface, and the conductive CuS out layer promotes electron transportation. This work might open a door for designing and synthesizing of hollow nanomaterials with mesoporous nano-shelled heterostructures consist of amorphous and crystalline phase for applications in electrochemical catalysis and energy conversion.