Construction of nanoporous gold/g-C₃N₄ heterostructure for electrochemical supercapacitor

Hybrids with two-dimensional and three-dimensional nanostructures have attracted great interest in the construction of supercapacitor electrodes due to their unique structural features. Graphitic carbon nitride (g-C₃N₄) nanosheets are deposited on the surface of a nanoporous gold (NPG) film via an electrochemical method to form a hybrid electrode of NPG/g-C₃N₄ with an ultra-thin, ultra-light and good flexible characteristics. The electrochemical tests show that the hybrid electrode exhibits a good supercapacitive performance, such as an admirable specific capacitance (440 F g⁻¹ at 2 A g⁻¹) in 0.5 M Na₂SO₄ solution and a favorable cycling durability (maintaining 98% capacity after 10000 cycles). More interesting, the NPG/g-C₃N₄ electrode displays a striking enhancement of supercapacitive performance with the increase of bending angle. This superior property can be attributed to the unique nanosheets on nanoporous structure by a strong interfacial effect between the defected Au atoms of NPG and g-C₃N₄.