Transition metal sulfides (TMSs) are widely recognized as promising catalysts for the oxygen evolution reaction (OER), yet their large–scale application is hindered by poor conductivity, severe aggregation and sluggish reaction kinetics. To address these issues, a ternary CoS 2 /FeS 2 /Ti 3 C 2 T x hybrid is rationally constructed via a three–in–one strategy, which simultaneously achieves the support introduction, morphology modulation and heterojunction construction. Structural characterizations reveal a hierarchical architecture composed of 1D CoS 2 nanorods, 0D FeS 2 nanoparticles and 2D conductive Ti 3 C 2 T x nanosheets, wherein CoS 2 and FeS 2 form a distinctive 1D/0D heterojunction. Density functional theory calculations demonstrate that strong electronic coupling at the CoS 2 /FeS 2 heterointerface accelerates electron transfer and optimizes the adsorption behavior of oxygen intermediates. Benefiting from the synergistic effects between the CoS 2 /FeS 2 heterojunction and the conductive Ti 3 C 2 T x support, the as–prepared CoS 2 /FeS 2 /Ti 3 C 2 T x hybrid exhibits elevated conductivity, promoted dispersibility and accelerated reaction kinetics, thus resulting in markedly improved OER performance as compared to the control samples. Additionally, the CoS 2 /FeS 2 /Ti 3 C 2 T x hybrid presents a remarkably low overpotential of 284 mV when used as the anode catalyst in a water–splitting device, demonstrating its outstanding applicability for overall water electrolysis. Overall, this work provides a viable strategy for engineering high–performance TMS–based electrocatalysts through heterointerface design and conductive support integration.
Chen et al. (Fri,) studied this question.