| dc.description.abstract | In recent years, the urgent need to address climate change necessitates the phasing out of fossil
fuels by 2050. To tackle the dual challenges of energy crises and environmental pollution,
electrocatalytic water splitting for hydrogen production has emerged as a key research area.
This process involves two half-reactions, with the oxygen evolution reaction (OER) being
particularly crucial due to its slow kinetics and high energy requirements. Metal–organic
frameworks (MOFs), characterized by high surface area and porosity, uniformly distribute
metal ions, providing abundant active sites for OER.
In this study, a novel C-MOF was synthesized using hydrothermal methods and analyzed with
single-crystal X-ray diffraction (SCXRD). Further, di-metallic CN-MOF and tri-metallic FCN-
MOF were synthesized via in-situ growth and applied as OER catalysts. The synergistic effects
among iron (Fe), cobalt (Co), and nickel (Ni) were investigated in 1 M KOH. The electronic
states of the catalysts′ active sites were found to be critical in determining their electrocatalytic
performance.
Additionally, platinum was deposited onto FCN-MOF using a simple sputtering method to
adjust the electronic configuration of the active metal centers, thereby reducing the energy
required for the OER. Characterization using powder X-ray diffraction (PXRD), scanning
electron microscopy (SEM), transmission electron microscopy (TEM), inductively coupled
plasma optical emission spectrometry (ICP-OES), and high-resolution X-ray photoelectron
spectroscopy (HRXPS) confirmed these modifications.
Compared to the unmodified tri-metallic FCN-MOF, the platinum-modified FCN-MOF-Pt1
exhibited superior electrocatalytic performance, with η10 and η500 reduced from 204 mV and
261 mV to 182 mV and 244 mV, respectively. The decrease in overpotential is attributed to theelevated oxidation states of Fe, Co, and Ni induced by the highly electronegative platinum.
Moreover, after continuous operation at a high current density of 500 mA cm−2 for 50 hours, the
current density of FCN-MOF-Pt1 decreased by only 7%. This stability is attributed to the in-situ growth method, which provides enhanced stability and tolerance under high current
densities by growing the MOF directly on the nickel foam skeleto | en_US |