Vacancy Occupation-Driven Polymorphic Transformation in Cobalt Ditelluride for Boosted Oxygen Evolution Reaction

Abstract

Transition-metal dichalcogenides (TMDs) hold great potential as an advanced electrocatalyst for oxygen evolution reaction (OER), but to date the activity of transition metal telluride catalysts are demonstrated to be poor for this reaction. In this study, we report the activation of CoTe2 for OER by doping secondary anions into Te vacancies to trigger a structural transition from the hexagonal to the orthorhombic phase. The achieved orthorhombic CoTe2 with partial vacancies occupied by P-doping exhibits an exceptional OER catalytic activity with an overpotential of only 241 mV at 10 mA cm–2 and a robust stability more than 24 h. The combined experimental and theoretical studies suggest that the defective phase transformation is controllable and allows the synergism of vacancy, doping as well as the reconstructed crystallographic structure, ensuring more exposure of catalytic active sites, rapid charge transfer, and energetically favorable intermediates. This vacancy occupation-driven strategy of structural transformation can also be manipulated by S- and Se-doping, which may offer useful guidance for developing tellurides-based electrocatalyst for OER.

Ultrathinning Nickel Sulfide with Modulated Electron Density for Efficient Water Splitting

“…[9][10][11][12][13][14] However, the sluggish kinetics of both hydrogen and oxygen evolution reactions (HER and OER) and the high overpotentials greatly limited its practical application. [15][16][17][18] At present, noble Pt metal and Ir/Ru-based oxides are the benchmark electrocatalysts to speed up the HER and the OER, respectively. [19][20][21][22][23] Unfortunately, the tremella-like Ni 3 S 2 /MnS-O with abundant oxygen vacancies, which was favorable for HER and OER.…”

“…[ 9–14 ] However, the sluggish kinetics of both hydrogen and oxygen evolution reactions (HER and OER) and the high overpotentials greatly limited its practical application. [ 15–18 ] At present, noble Pt metal and Ir/Ru‐based oxides are the benchmark electrocatalysts to speed up the HER and the OER, respectively. [ 19–23 ] Unfortunately, the widespread application of these precious catalysts is seriously restricted by their low natural abundance and high cost.…”

Accurately Regulating the Electronic Structure of NixSey@NC Core–Shell Nanohybrids through Controllable Selenization of a Ni‐MOF for pH‐Universal Hydrogen Evolution Reaction

“…[ 18–20 ] Meanwhile, utilizing MOFs as templates or precursors, the active catalysts could not only well inherit intrinsic structure advantages of MOFs, but also protect them from aggregation with the homogeneously dispersed transition metal ions in the MOFs’ precursors. [ 21,22 ] Generally, there are two main approaches to tune the electronic structure of TMSs@HCM core–shell nanohybrids to enhance HER performances. One effective method is to functionalize the HCM shell by controlling the heteroatom species as well as the amount of heteroatoms, which could effectively regulate the interfacial electronic structure of TMSs@HCM nanohybrids and facilitate the adsorption and desorption of reaction intermediates.…”

Binder‐Free Air Electrodes for Rechargeable Zinc‐Air Batteries: Recent Progress and Future Perspectives

“…Such interfaces are believed to be beneficial to enhance the OH − adsorption ability and reduce the Gibbs free energy of the reaction intermediate, leading to an improved OER catalytic activity. [ 21,108,109 ]…”

“…[ 12–15 ] Although a large number of highly efficient electrocatalysts for the ORR or the OER have been reported, it is still a challenging task to effectively catalyze both ORR and OER by a bifunctional electrocatalyst. [ 16–25 ] Recently, a strategy in battery design has been delivered to address the dilemma, where the Zn‐air battery possesses three electrodes comprising a Zn anode placed between decoupled ORR electrode and OER electrode. [ 26–29 ] However, the complex cell design and depressed volumetric/power energy density are unfavorable for the commercialization.…”