Identifying Dense NiSe₂/CoSe₂ Heterointerfaces Coupled with Surface High‐Valence Bimetallic Sites for Synergistically Enhanced Oxygen Electrocatalysis

Abstract

Constructing heterostructures with abundant interfaces is essential for integrating the multiple functionalities in single entities. Herein, the synthesis of NiSe2/CoSe2 heterostructures with different interfacial densities via an innovative strategy of successive ion injection is reported. The resulting hybrid electrocatalyst with dense heterointerfaces exhibits superior electrocatalytic properties in an alkaline electrolyte, superior to other benchmarks and precious metal catalysts. Advanced synchrotron techniques, post structural characterizations, and density functional theory (DFT) simulations reveal that the introduction of atomic‐level interfaces can lower the oxidation overpotential of bimetallic Ni and Co active sites (whereas Ni2+ can be more easily activated than Co2+) and induce the electronic interaction between the core selenides and surface in situ generated oxides/hydroxides, which play a critical role in synergistically reducing energetic barriers and accelerating reaction kinetics for catalyzing the oxygen evolution. Hence, the heterointerface structure facilitates the catalytic performance enhancement via increasing the intrinsic reactivity of metallic atoms and enhancing the synergistic effect between the inner selenides and surface oxidation species. This work not only complements the understanding on the origins of the activity of electrocatalysts based on metal selenides, but also sheds light on further surface and interfacial engineering of advanced hybrid materials.

3D CoSe@C Aerogel as a Host for Dendrite‐Free Lithium‐Metal Anode and Efficient Sulfur Cathode in Li–S Full Cells

“…[34][35][36] Among the them, CoSe has higher electrical conductivity and excellent catalytic properties compared to many highly active Co-based catalysts, including hydroxides, oxides, and sulfides, but it has received less attention for application in Li-S batteries. [37][38][39] In this communication, a 3D carbon aerogel decorated with lithiophilic and catalytic cobalt selenide nanoparticles (CoSe@C) is presented as an advanced host for dendrite-free lithium-metal anode and highly efficient sulfur cathode. With this design, CoSe@C exhibits several appealing characteristics.…”

Challenges and Strategy on Parasitic Reaction for High‐Performance Nonaqueous Lithium–Oxygen Batteries

“…The enhancement can be assigned to the increase in the number of accessible active sites, accelerated mass/charge transfer, and optimization of the adsorption ability of intermediates, thus advancing the reaction kinetics and boosting the catalytic activity. [200] Constructing heterostructure interface is an available way to optimize the adsorption energy of intermediate LiO 2 , thus effectively regulating the formation mechanism of Li 2 O 2 in Li-O 2 battery. As a result of unstable strongly solvated electrolytes toward the reactive O 2 − radical leading to undesirable side reactions, searching an efficient method to achieve the solvation pathway of Li 2 O 2 in low-donor-number (DN) solvents is capable of reducing the parasitic reaction to a certain extent.…”

微纳结构过渡金属化合物能源转化电催化剂研究进展

“…As congeners, transition metal selenides have similar physiochemical properties with sulfides. Moreover, compared with oxides and sulfides, transition metal selenides exhibit a metallic nature with a faster electron transfer ability, which significantly favors the electrochemical reaction process [76][77][78][79][80][81]. However, their composite and structural properties are still needed to be improved to compete with noble metal-based electrocatalysts.…”