Electrochemical performance and kinetics of Mn, Ni, Fe, and Co-loaded covalent triazine frameworks for oxygen evolution reaction in alkaline media

A highly active, cost-effective, and stable oxygen evolution reaction (OER) electrocatalyst is crucial for overcoming the sluggish kinetics of the OER in water electrolyzers, thereby enabling the efficient conversion of renewable energy into hydrogen as a storable form of chemical energy. In this study, a covalent triazine framework (CTF) was synthesized from 1,3-dicyanobenzene (mDCB) using ZnCl2 via a two-step ionothermal process at elevated temperatures (400 degrees C and 600 degrees C). The resulting mDCB-CTF, with a high specific surface area (2271 m(2) g(-1)) and total pore volume (1.77 cm(3) g(-1)), was employed as a support platform for doping with approximately 1 wt% of various transition metals (Mn, Ni, Fe, and Co) via a wet impregnation method, followed by thermal treatment at 600 degrees C under a nitrogen atmosphere. The results demonstrate that even a low metal content (1 wt%) significantly enhances OER performance by improving both the onset potential and current density. Among the metal-doped catalysts, Ni-mDCB exhibited the best OER activity, following the trend: Ni-mDCB > Fe-mDCB > Co-mDCB > Mn-mDCB. This superior performance is attributed to its lowest charge transfer resistance (4384 Omega), highest double-layer capacitance (154 mu F), corresponding to the largest electrochemically active surface area (3.85 cm(2)), and enhanced conductivity, despite its lowest crystallinity. This study highlights that minimal metal doping can substantially improve the OER performance and kinetics, emphasizing the critical role of metal incorporation in tuning electrocatalytic properties.