Transition metal selenides are a highly promising class of electrocatalysts in the field of alkaline oxygen evolution reactions (OER). However, due to the weak catalytic ability of intrinsic active sites and slow kinetic driving forces, the OER performance of single metal selenides is still unsatisfactory. Herein, we prepared a novel iron doped cobalt selenide nanospheres catalyst (FeCoSe) by introducing Fe in situ into CoSe during the solvothermal reaction process using a doping strategy. Density functional theory (DFT) calculations demonstrate that the incorporation of Fe effectively optimizes the d-band center of CoSe, thereby enhancing the catalyst's adsorption capacity for intermediates, reducing the reaction barrier for OER, accelerating the kinetics rate of OER, and ultimately improving the overall catalytic performance for OER. The optimal catalyst (FeCoSe-1:2) demonstrates exceptional OER performance in 1 M KOH electrolyte, exhibiting a low overpotential of 250 mV at a current density of 10 mA cm −2 and a small Tafel slope of 44 mV dec −1 , surpassing the performance of the cobalt selenide. The catalyst also demonstrates excellent long-term stability during the OER process. This study will provide valuable reference for the development of durable alkaline OER catalysts, thereby facilitating the fabrication of advanced energy devices in future.
The urgent need to develop efficient, durable, and cost-effective oxygen evolution reaction (OER) catalysts for energy conversion and storage has prompted extensive research. Currently available commercial noble metal-based OER catalysts are expensive and exhibit limited long-term stability. In this study, boron-doped diamond composites (BDDCs) consisting of CoFe and CoFe 2 C nanoparticles supported by boron-doped diamond (BDD) particles have been prepared. The BDDC catalyst, prepared through a straightforward annealing process, exhibits exceptional durability (up to 72 h at 10 mA cm −2 ), a low overpotential (306 mV at 10 mA cm −2 ), and modest Tafel slope (58 mV dec -1 ). The coherent interfaces between CoFe/CoFe 2 C nanoparticles and the BDD substrate are essential for enhancing the OER performance. The fabrication method and composite structures presented in this study may facilitate the design and production of promising catalysts.
Slow oxygen evolution reaction (OER) and material transport impedance in catalyst-coated membrane (CCM) are major challenges for the practical proton exchange membrane water electrolyzer (PEMWE). Herein, we present a novel OER catalyst by polyether-derived composite oxide pyrolysis with a multilevel porous support and abundant oxygen vacancies to boost efficiency and durability in water electrolysis. The formation of a heterointerface with abundant oxygen vacancies in IrO x improves the catalytic activity and prevents IrO x from peroxidation. Furthermore, the unique pore structure of the support facilitates the mass transport of the anode catalyst layer during water electrolysis at high current density, and the mass transport resistance of the water electrolyzer is only 0.0154 Ω cm 2 at 1.5 A cm −2 . When used in a PEMWE, the prepared electrocatalysts have an impressive electrochemical performance of 1.87 V at 3·A cm −2 with an Ir loading of only 0.91 mg cm −2 . This approach highlights the importance of oxygen vacancies and transportation in the catalyst-support interface, providing a promising solution for high-rate practical water electrolysis. Graphical
Efficient OER supported catalysts enriched with oxygen vacancies for PEMWE applications
危险品化学品经营许可证（带存储）