We report an efficient energy storage electrode based on well-defined, interconnected NiO nanosheets (NiO-NS) grown directly on a mesoporous TiN (meso-TiN) film via a solvothermal method. A mesoporous TiO 2 (meso-TiO 2 ) film is prepared using a graft copolymer template and then thermally annealed in ammonia at 800 °C to convert meso-TiO 2 into meso-TiN. The ultrathin interconnected NiO-NS provide a large surface area and effective electron pathway, which enhance their specific capacitance and electrochemical properties. In contrast, a less-organized structure with poor homogeneity, low porosity and some cracks is formed for dense-TiN film prepared without the PVC-g-POEM. The meso-TiN film acts as an efficient conductive support to grow the NiO-NS and enhances the diffusion of electron/electrolyte ions. Despite its low thickness (<1.3 μm), the NiO-NS/meso-TiN supercapacitor exhibits a high capacitance of 104 mF cm −2 and good cycle stability (86% capacitance retention) owing to the synergetic effects of the NiO-NS and meso-TiN heteronanostructure. The NiO-NS/meso-TiN film is also applied to a flexible substrate and exhibits no cracks after bending; thus, our work provides an efficient way to design flexible energy storage devices using graft-copolymer-directed heteronanostructures.
Bibliographical noteFunding Information:
This work was supported by the Converged Energy Materials Research Center program of Defense Acquisition Program Administration and Agency for Defense Development, and the Center for Advanced Meta-Materials (CAMM) (NRF-2014M3A6B3063716) funded by the National Research Foundation (NRF).
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films