Crumpled fibrous graphdiyne network decorated metal–organic framework: a promising heterostructure for improved energy storage performance

Abstract

Graphdiyne (GDY) is an emerging two-dimensional (2D) carbon material having an ideal structure and unique sp- and sp²-hybridized linkages as compared to traditional carbon-based materials. However, preparing a new 2D hybrid material that is processable at low temperatures with a metal–organic framework (MOF) is challenging as compared to other carbon-based materials prepared at high temperatures and under harsh conditions. Herein, we explored crumpled fibrous hydrogen-substituted graphdiyne (HsGDY) wrapped on the surface of Ni-MOFs (MOF@HsGDY) for supercapacitor applications. HsGDY functions as a support for the MOF in the electrochemical process, which creates efficient charge transfer at the interface of the MOF. HsGDY is an efficient substrate with uniform porosity and excellent chemical stability. The uniform porosity of HsGDY creates extensive charge-transfer nanochannels and improves the specific capacitance with the MOF hybrid. Electrochemical results indicate that the MOF@HsGDY-based electrode attained a specific capacitance of 982 F g⁻¹ with outstanding cycling stability. Besides, an ASC device was fabricated which delivered an energy density of 43.3 W h kg⁻¹. To the best of our knowledge, HsGDY with a MOF hybrid structure has not been previously explored for supercapacitor applications. This study findings prove that HsGDY can provide a new route to solve the problem of MOF stability in electrochemical processes.