Non-Covalent Functionalization of Graphene Oxide-Supported 2-Picolyamine-Based Zinc(II) Complexes as Novel Electrocatalysts for Hydrogen Production

Three mononuclear 2-picolylamine-containing zinc(III) complexes viz [(2-PA)2ZnCl]2(ZnCl4)] (Zn1), [(2-PA)2Zn(H2O)](NO3)2] (Zn2) and [Zn(2-PA)2(OH)]NO3] (Zn3) were synthesized fully characterized. Spectral X-ray structural characteristics showed that the Zn1 complex has a square-pyramidal coordination environment around zinc(II) core. The hydroxide Zn3 was non-covalently functionalized with few layers of graphene oxide (GO) sheets, formed by exfoliation GO in water. resulting Zn3/GO hybrid material characterized FT-IR, TGA-DSC, SEM-EDX powder diffraction. way interaction been established through density functional theory (DFT) calculations. Both experimental theoretical findings indicate that, on surface GO, forms complete double-sided adsorption layer. its form have individually investigated as electrocatalysts for hydrogen evolution reaction. heterogenized supported glassy carbon (GC) variable loading densities (0.2, 0.4 0.8 mg cm−2) to electrodes. These electrodes tested molecular reaction (HER) using linear sweep voltammetry (LSV) electrochemical impedance spectroscopy (EIS) 0.1 M KOH. Results both GC-Zn3 GC-Zn3/GO catalysts HER are highly active, increase catalyst’s density, this catalytic activity enhances. high low onset potential −140 mV vs. RHE exchange current 0.22 mA cm−2 is achieved highest (0.8 cm−2). To achieve 10 cm−2, an overpotential 240 needed.