A Dual-Function Catalyst for Efficient Electrocatalytic Water Splitting: Harnessing the Synergy of...

A robust cobalt-based PN³P-pincer molecular complex is introduced that serves as an efficient bifunctional electrocatalyst for electrochemical water splitting. This water-soluble, electron-deficient cobalt PN³P-pincer complex demonstrates impressive catalytic activity for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), utilizing metal-ligand cooperation to optimize the overpotential for water splitting. Importantly, the (pseudo)dearomatized species, with a nucleus-independent chemical shift (NICS) value of -14.6, show excellent OER activity, while the aromatized species achieve superior HER performance at an exceptionally low overall overpotential (≈0.46 V), outperforming other reported cobalt-based molecular catalysts. Stability assessments confirm the catalyst's durability during prolonged electrolysis, exhibiting minimal decomposition and high Faradaic efficiency. Insights from density functional theory (DFT) calculations demonstrate a lower-energy pathway for the (pseudo)dearomatized complex in the OER, consistent with experimental results. This research emphasizes the promise of aromaticity-controlled molecular design for enhancing electrocatalytic water splitting, contributing to renewable energy applications and sustainable hydrogen production.