Carboxylated Group Effect of Graphene Oxide on Capacitance Performance of Zr-Based Metal Organic Framework Electrodes

Graphene oxide (GO) has many oxygen functional groups and high specific surface area. GO-OOH was prepared from GO by carboxylation that the hydroxyl and epoxy groups on the GO surface were converted into carboxyl groups. Zr-bdc MOF (metal organic framework of zirconium metal combined with terephthalic acid ligands modulated by acetic acid) has good thermal stability (up to 773 k) and excellent chemical stability. In order to obtain the larger pore volume and specific surface area, Zr-bdc/GO-OOH and Zr-bdc/GO were synthesized by hydrothermal reaction from the carboxylated GO (GO-OOH) with zirconium ion precursor of Zr-bdc MOF. The morphology, structure and crystallinity of the composites were investigated by Fourier transform infrared spectroscopy (FT-IR) and field emission scanning electron microscopy (FE-SEM). The electrochemical properties were characterized by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS) test. Graphic Abstract: [Figure not available: see fulltext.]