Solvent Effect on the Fabrication of POMs-Based MOFs Microspheres: Dual-Function in Electrocatalytic Hydrogen Evolution and Catalytic Reduction of Cr6+.

In this study, a novel polyoxometalates-based metal-organic frameworks (POMOFs) microsphere, that is [Ni(phen)H₂O]·V₂O₆ (phen is o-phenanthroline)_, have been successfully fabricated by one-pot simple hydro(solvent)thermal reaction through regulating different solvent ratios (H₂O/EtOH). The experimental results show that the solvent effect has a significant effect on the micro-morphology and the catalytic activity of the materials. The dual-function in electrocatalytic hydrogen evolution and catalytic reduction of Cr⁶⁺ of the as-prepared POMOFs microspheres have been also studied. The POMOF(V,Ni)_3 catalyst prepared in the medium of pure ethanol have the best catalytic activity, in which the overpotential of 159 mV for the electrode is comparable to that of MoS₂-based electrode material, and the rate constant k reaches 0.14 in the process of catalytic reduction of Cr⁶⁺. In this study, a novel polyoxometalates-based metal-organic frameworks (POMOFs) microsphere [Ni(phen)H₂O]·V₂O₆ have been successfully fabricated by one-pot simple hydro(solvent)thermal reaction through regulating different solvent ratios. The dual-function in electrocatalytic hydrogen evolution and catalytic reduction of Cr⁶⁺ of the as-prepared sample have been also studied. [ABSTRACT FROM AUTHOR]