Cobalt‐Based ZIF‐67 Metal Organic Framework for Enhanced Photoelectrochemical Performance

This investigation explores the efficacy of Zeolitic Imidazolate Framework‐67 (ZIF‐67), a cobalt‐centric metal‐organic framework, in photoelectrocatalytic hydrogen generation. A comprehensive analysis of ZIF‐67's structural, morphological, and photoelectrochemical attributes is conducted using techniques such as scanning electron microscopy (SEM), x‐ray diffraction (XRD), Brunauer‐Emmett‐Teller (BET) surface area analysis, and ultraviolet‐visible (UV–vis) absorption spectroscopy. The photoelectrochemical performance of ZIF‐67 is evaluated on various substrates, including UV‐ozone treated fluorine‐doped tin oxide (FTO) substrates and carbon paper. This study demonstrates enhanced photoelectrocatalytic performance from ZIF‐67 through strategic substrate engineering. UV‐ozone treated FTO/ZIF‐67 achieves ‐138 µA/cm 2 (five times improvement vs untreated FTO), while ZIF‐67/carbon black delivers ‐390 µA/cm 2 (4 times higher than literature ZIF‐67/BiVO 4 composites). Comprehensive analysis (SEM, XRD, BET: 1416 m 2 /g, UV–vis: 2.03 eV bandgap) reveals how surface hydrophilicity and conductive additives enhance charge transfer, validated by EIS, and chronoamperometry. These findings establish substrate optimization as a powerful strategy for advancing MOF‐based photoelectrocatalytic hydrogen production.