فهرست نشریات علمی دسترسی آزاد ایران

It is also critical to develop highly efficient, cost-competitive, and stable electrocatalysts that facilitate the oxygen evolution reaction (OER) to promote sustainable hydrogen production. In this work, a bimetallic nickel–zinc metal–organic framework (MOF-74) was synthesized and in situ grown on nickel foam (NF) via solvothermal reaction to construct an NF-based binder-free electrode. The resultant Ni–Zn MOF-74/NF exhibited optimized OER performance, with 45 mA cm⁻² at 1.6 V versus the reversible hydrogen electrode (RHE), a small Tafel slope of 72 mV dec⁻¹, and superior stability in long-term operation of 6 hours at 1.55 V versus RHE in a 0.1 M KOH solution. The Ni–Zn MOF-74/NF electrode shows enhanced OER activity and an increase in electrochemical surface area, indicated by 40–80 times higher Cdl (20–40 mF cm⁻²) than the bare Ni foam (0.49 mF cm⁻²). Electrochemical impedance spectroscopy (EIS) provided clear evidence of a marked reduction in charge-transfer resistance and rapid electron transfer at the MOF–NF interface. In addition, quantitative structure–property relationship (QSPR) modeling was employed to establish correlations between structural parameters—void fraction (VF), framework density (ρ), and largest cavity diameter (LCD)—and accessible surface area (ASA). This model demonstrated strong predictive ability (R²_train = 0.915, R²_test = 0.932) and identified VF as significantly impacting ASA and OER performance. Synergistic incorporation of Zn altered the electronic environment around Ni centers and increased porosity, thereby enhancing the formation of high-valence Ni species and optimizing OH⁻ and O₂ desorption. This experimental–theoretical study illuminates a rational design pathway for preparing high-performance MOF-based electrocatalysts.