Fabrication of a polyoxotungstate/metal–organic framework/phosphorus-doped reduced graphene oxide nanohybrid modified glassy carbon electrode by electrochemical reduction and its electrochemical properties

Hybrid nanocomposites based on polyoxometalates (POMs), metal–organic frameworks (MOFs), and graphene oxide (GO) have a unique set of properties. They have specific properties such as high acidity, oxygen-rich surface, and good redox capability from POMs. In contrast, they do not have weaknesses of POMs such as a low surface area, and high solubility in aqueous media. Herein, a novel organic–inorganic nanohybrid compound based on H(3)PW(12)O(40) (PW(12)), a Co-based MOF, and GO was prepared. The prepared hybrid nanocomposite (PW(12)/MOF/GO) was characterized using different techniques. Then, a PW(12)/MOF/GO nanocomposite modified glassy carbon electrode (GCE) was fabricated by the drop-casting method and next was dried at room temperature. Then, the PW(12)/MOF/GO/GCE was subjected to electrochemical reduction at a constant potential of −1.5 V, in 0.1 M H(3)PO(4) solution containing 0.10% w/v PW(12)/MOF/GO additive. The morphology, electrochemical activity, and stability of the modified electrode (PW(12)/MOF/P@ERGO/GCE) were studied with FE-SEM coupled with EDS, CV, and amperometry. The obtained results confirmed that the PW(12)/MOF/P@ERGO/GCE could be effective in hydrogen evolution reaction (HER). The electrochemical activity of the PW(12)/MOF/P@ERGO/GCE due to the desirable microstructure of the electrocatalyst (e.g. high active surface area and homogeneous distribution of the PW(12)/MOF/P@ERGO), and also the synergistic effect of the blocks, is more than those of PW(12)/GCE, MOF/GCE, PW(12)/MOF/GCE, and P@ERGO/GCE. Moreover, the PW(12)/MOF/P@ERGO/GCE showed an excellent long-term stability under the air atmosphere.