Layer-by-layer inkjet printing GO film anchored Ni(OH)2 nanoflakes for high-performance supercapacitors

Inkjet printing of graphene film with the characteristic of low-cost, light weight, thin thickness and high conductivity has been gradually recognized. In this work, we report a novel route of preparation Ni(OH)2/RGO/Ni(OH)2/RGO composites electrode with layer-by-layer construction, which was synthesized by a reduplicative inkjet printing method and followed by a facile hydrothermal process. The first-layer RGO film with large surface area connects the first-layer Ni(OH)2 and nickel foam as a new substrate without any addition. The second-layer RGO film plays an important role in bridging the lower and upper Ni(OH)2 sheets, and arranging the upper Ni(OH)2. The as-prepared electrode with controllable microstructures exhibits excellent electrochemical performance. An asymmetric supercapacitor (ASC) device is assembled with the Ni(OH)2/RGO/Ni(OH)2/RGO composites, which reveals remarkable energy density and power density (64.8 Wh kg−1 at 800 W kg−1 and 30.7 Wh kg−1 at 16,000 W kg−1).