Electrochemical synergies of Fe–Ni bimetallic MOF CNTs catalyst for OER in water splitting

Abstract

This work describes electrocatalytic behavior of amiable and economical iron nickel 2-amioterephthalic acid metal organic framework (FeNiNH2BDC MOF) and its 2–6 wt % carbon nanotubes (CNTs) composites for oxygen evolution reaction (OER) in an alkaline media. Systematic structural and morphological analysis of solvothermally fabricated Iron (Fe) and Nickel (Ni) based MOF and their CNTs composites was carried out by Fourier Transform Infrared Spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray powder diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Brunauer–Emmett–Teller (BET) and energy dispersive X-ray spectroscopy (EDX) techniques. Synergetic effect of bimetallic metal organic framework (MOF) and conductive CNTs support improves the catalytic response of MOF. FeNiNH2BDC-5 wt % CNTs composite demonstrated current density of 10 mA/cm2 at an over potential (η) 0.22 V and onset potential of 1.36 V vs RHE, comparable with RuO2 state-of-the-art catalytic material for oxygen evolution reaction in a fuel cell. Furthermore, FeNiNH2BDC-5 wt % CNTs composite tafel slope of 68.50mV/dec and 0.67s−1 turnover frequency (TOF) ascertain it as a promising alternative candidate towards costly Pt, Pd, Ir and Ru based catalysts.