Carbothermal Shock Synthesis of High Entropy Oxide Catalysts: Dynamic Structural and Chemical Reconstruction Boosting the Catalytic Activity and Stability toward Oxygen Evolution Reaction

Advanced Energy Materials, Год журнала: 2022, Номер 12(35)

Опубликована: Июль 27, 2022

Abstract Mixed transition‐metals (TM) based catalysts have shown huge promise for water splitting. Conventional synthesis of nanomaterials is strongly constrained by room‐temperature equilibria and Ostwald ripening. Ultra‐fast temperature cycling enables the metastable metallic phases high entropy alloy nanoparticles, which later transform to oxide/hydroxide nanoparticles upon use in aqueous electrolytes. Herein, an situ non‐noble metal oxide (HEO) on carbon fibers rapid Joule heating quenching reported. Different compositions ternary senary (FeNiCoCrMnV) HEO show higher activity towards catalyzing oxygen evolution reaction (OER) compared a noble IrO 2 catalyst. The synthesized also two orders magnitude stability than , due stronger carbide‐mediated intimacy with substrate, activated through OER process. Alloying elements Cr, Mn V affect promoting different oxidation states catalytically active TM (Fe, Ni Co). Dissolution less stable (Mn, Cr) leads enhancements activity. Dynamic structural chemical perturbations activate under conditions, leading enlargement ECSA forming mixed single atom ultra‐fine oxyhydroxide HEOs.

Язык: Английский

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Regulating the Local Spin State and Band Structure in Ni₃S₂ Nanosheet for Improved Oxygen Evolution Activity

Advanced Functional Materials, Год журнала: 2022, Номер 32(18)

Опубликована: Янв. 24, 2022

Abstract The separate modulation of the adsorption *O and *OOH is challenging in oxygen evolution reaction (OER), which results a large overpotential slow kinetics. To balance two active species, here, way to regulate local spin state band structure simultaneously Ni 3 S 2 nanosheets reported. adequate doping W heteroatoms causes electron depletion from site, modulates e g electrons, weakening *O. Additionally, introduction vacancies contributes upshift d center, strengthens *OOH. In this manner, for intermediates optimized, resulting considerably improved 246 mV at 100 mA cm −2 Tafel slope 66 dec −1 . This work provides insights into exploration OER catalysts through synergistic structure.

Язык: Английский

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Dual-atom catalysts for oxygen electrocatalysis

Nano Energy, Год журнала: 2022, Номер 104, С. 107927 - 107927

Опубликована: Окт. 28, 2022

Язык: Английский

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A Review of Transition Metal Boride, Carbide, Pnictide, and Chalcogenide Water Oxidation Electrocatalysts

Chemical Reviews, Год журнала: 2023, Номер 123(23), С. 12795 - 13208

Опубликована: Ноя. 15, 2023

Transition metal borides, carbides, pnictides, and chalcogenides (X-ides) have emerged as a class of materials for the oxygen evolution reaction (OER). Because their high earth abundance, electrical conductivity, OER performance, these electrocatalysts potential to enable practical application green energy conversion storage. Under potentials, X-ide demonstrate various degrees oxidation resistance due differences in chemical composition, crystal structure, morphology. Depending on oxidation, catalysts will fall into one three post-OER electrocatalyst categories: fully oxidized oxide/(oxy)hydroxide material, partially core@shell unoxidized material. In past ten years (from 2013 2022), over 890 peer-reviewed research papers focused electrocatalysts. Previous review provided limited conclusions omitted significance "catalytically active sites/species/phases" this review, comprehensive summary (i) experimental parameters (e.g., substrates, loading amounts, geometric overpotentials, Tafel slopes, etc.) (ii) electrochemical stability tests post-analyses publications from 2022 is provided. Both mono polyanion X-ides are discussed classified with respect material transformation during OER. Special analytical techniques employed study reconstruction also evaluated. Additionally, future challenges questions yet be answered each section. This aims provide researchers toolkit approach showcase necessary avenues investigation.

Язык: Английский

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Surface chemical reconstruction of hierarchical hollow inverse-spinel manganese cobalt oxide boosting oxygen evolution reaction

Chemical Engineering Journal, Год журнала: 2021, Номер 431, С. 133829 - 133829

Опубликована: Ноя. 26, 2021

Язык: Английский

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