In Situ Unravelling NiOOH Species on Flower‐Like NiFeCo LDH/Nb 2 CT x for Ameliorated Solar‐Powered Bifunctional Electrocatalytic Benzyl Alcohol Oxidation Coupled with Hydrogen Evolution

Abstract Developing bifunctional electrocatalysts from earth‐abundant first‐row transition metals for large‐scale hydrogen production through water electrolysis is both promising and challenging. This study presents a ternary layered double hydroxide (LDH) as a bifunctional electrocatalyst for the hydrogen evolution reaction (HER) and benzyl alcohol oxidation (BAOR). The synergy between 2D NiFeCo LDH and non‐Ti‐based Nb 2 CT x MXene enhances electrochemical performance. The electrocatalyst achieves excellent results with a low potential of 1.5 V versus RHE at 100 mA cm⁻ 2 for BAOR, an overpotential of 320 mV at 50 mA cm⁻ 2 for HER, and stability over 100 h. A solar cell‐powered HER||BAOR system shows faradaic efficiency of ≈73.92% for benzaldehyde production and solar‐to‐hydrogen (STH) efficiency of ≈39.67%. In situ Raman analysis identifies the oxyhydroxide group as the real catalytic active site during BAOR. These findings offer valuable insights for linking fundamental research with technological innovation to address global challenges.