"Two-dimensional vertical" strategy enhances the performance of MOF in supercapacitors

Metal-organic frameworks (MOFs) have received wide attention due to their diversity in structure and function. The MOF material has a high specific surface area and a large number of active sites, and thus can be used as an electrode of an electrochemical energy storage device. However, the low conductivity and the inhomogeneity of growth orientation caused by traditional electrode preparation methods limit the advantages of MOF materials. The unique synthesis method can completely solve the problem of poor conductivity and disordered orientation of the MOF material, which has important scientific significance and huge potential application value.

In the recent publication of Communications Chemistry’s recently published co-oriented two dimensional metal-organic frameworks for packaging enhanced supercapacitive performance, Prof. Weitao Zheng, Prof. Wei Zhang, and Dr. Wei Deng of Jilin University have developed nano-carbon walls prepared by plasma-enhanced chemical vapor deposition. As a template and a current collector, a two-dimensional MOF material having a vertical structure was successfully synthesized by combining with a MOF precursor. Based on the first-principle calculations of the growth mechanism of MOF, it was found that the precursors of the synthetic MOF adsorbed on the edges of the carbon wall and grew along the edges. Metal ions and organic ligands continued to follow the direction parallel to the carbon wall. Assembled and finally formed a MOF with a vertical structure. This result not only solves the problem of growing misaligned orientation, but also effectively improves its conductivity by compounding with carbon materials. The synthesis method is very simple and efficient. The research team will prepare a two-dimensional MOF with a vertical structure as an electrode of a supercapacitor, and the maximum specific capacitance may reach 1962 Fg-1 at a current density of 1 Ag-1, and at a high current density of 32 Ag-1, Capacitance can also be as high as 996 Fg-1. Compared with the same MOF material electrode prepared by the traditional method, a great leap in performance was achieved. This efficient and simple synthesis method also broadens the application prospects of MOF materials in the energy storage field. (Source: Science Network)