Valence Oscillation of Ru Active Sites for Efficient and Robust Acidic Water Oxidation

Advanced Materials, Год журнала: 2023, Номер 35(48)

Опубликована: Сен. 6, 2023

The continuous oxidation and leachability of active sites in Ru-based catalysts hinder practical application proton-exchange membrane water electrolyzers (PEMWE). Herein, robust inter-doped tungsten-ruthenium oxide heterostructures [(Ru-W)Ox ] fabricated by sequential rapid metal thermomigration processes are proposed to enhance the activity stability acidic oxygen evolution reaction (OER). introduction high-valent W species induces valence oscillation Ru during OER, facilitating cyclic transition states maintaining operation sites. preferential electronic gain heterostructure significantly stabilize RuOx on WOx substrates beyond Pourbaix limit bare RuO2 . Furthermore, asymmetric Ru-O-W units generated around interface adsorb intermediates synergistically, enhancing intrinsic OER activity. Consequently, (Ru-W)Ox not only demonstrate an overpotential 170 mV at 10 mA cm-2 excellent 300 h electrolytes but also exhibit potential for applications, as evidenced stable 0.5 A PEMWE.

Язык: Английский

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Recent Advancements in Electrochemical Hydrogen Production via Hybrid Water Splitting

Advanced Materials, Год журнала: 2023, Номер 36(4)

Опубликована: Окт. 10, 2023

Abstract As one of the most promising approaches to producing high‐purity hydrogen (H 2 ), electrochemical water splitting powered by renewable energy sources such as solar, wind, and hydroelectric power has attracted considerable interest over past decade. However, electrolysis process is seriously hampered sluggish electrode reaction kinetics, especially four‐electron oxygen evolution at anode side, which induces a high overpotential. Currently, emerging hybrid strategy proposed integrating thermodynamically favorable electro–oxidation reactions with cathode, providing new opportunity for energy–efficient H2 production. To achieve highly efficient cost–effective toward large–scale practical H production, much work been continuously done exploit alternative anodic oxidation cutting–edge electrocatalysts. This review will focus on recent developments production coupled reactions, including choice substrates, investigation electrocatalytic materials, deep understanding underlying mechanisms. Finally, some insights into scientific challenges now standing in way future advancement technique are shared, hope inspiring further innovative efforts this rapidly growing field.

Язык: Английский

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Urea catalytic oxidation for energy and environmental applications

Chemical Society Reviews, Год журнала: 2024, Номер 53(3), С. 1552 - 1591

Опубликована: Янв. 1, 2024

This review evaluates state-of-the-art advances in electrocatalytic and photo(electro)catalytic urea oxidation from fundamentals materials to energy environmental applications.

Язык: Английский

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Fluorinated Ni‐O‐C Heterogeneous Catalyst for Efficient Urea‐Assisted Hydrogen Production

Advanced Functional Materials, Год журнала: 2023, Номер 33(44)

Опубликована: Июнь 20, 2023

Abstract Constructing multiple heterogeneous structures allows for improving the electrocatalytic activity of NiO by incorporating active sites. Unfortunately, poor conductivity makes efficient charge transfer within difficult, thereby inhibiting improvement its intrinsic activity. Herein, F‐doped NiO/Ni@C catalyst (F‐NiO/Ni@C) is fabricated via a new organic‐inorganic hybrid approach, showing both advanced hydrogen evolution reaction (HER) and urea oxidation (UOR) The targeted F‐doping increases electron delocalization, facilitates from Ni to at nano‐interfaces. This interphase synergy provides ready‐to‐use F‐NiO sites, allowing F‐NiO/Ni@C achieve optimum H* adsorption Gibbs free energy HER lower barrier UOR. As result, as‐configured || cell requires an ultra‐low voltage 1.37 V 10 mA cm −2 in alkaline media (with 0.3 M urea), outperforming state‐of‐the‐art benchmark Pt/C|| RuO 2 (1.45 V). study reveals positive impact anion doping on useful guidelines designing monometallic catalysts UOR as well generation.

Язык: Английский

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Understanding the bifunctional catalytic ability of electrocatalysts for oxygen evolution reaction and urea oxidation Reaction: Recent advances and perspectives

Chemical Engineering Journal, Год журнала: 2023, Номер 471, С. 144660 - 144660

Опубликована: Июль 11, 2023

Язык: Английский

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Constructing CoO/Mo₂C Heterostructures with Interfacial Electron Redistribution Induced by Work Functions for Boosting Overall Water Splitting

Small, Год журнала: 2023, Номер 19(49)

Опубликована: Авг. 23, 2023

Space charge transfer of heterostructures driven by the work-function-induced built-in field can regulate electronic structure catalysts and boost catalytic activity. Herein, an epitaxial heterojunction catalyst CoO/Mo2 C with interfacial electron redistribution induced work functions (WFs) is constructed for overall water splitting via a novel top-down strategy. Theoretical simulations experimental results unveil that WFs-induced facilitates from CoO to Mo2 through formed "Co─C─Mo" bond at interface C, achieving redistribution, further optimizing Gibbs free energy primitive reaction step then accelerating kinetics hydrogen evolution (HER). As expected, effects exhibits excellent HER activity only needing overpotential 107 mV achieve 10 mA cm-2 stability 60-h continuous catalyzing. Besides, assembled behaves outstanding performance toward (1.58 V ). This provides possibility designing materials based on arising application in other fields.

Язык: Английский

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Modulation Strategies for the Preparation of High‐Performance Catalysts for Urea Oxidation Reaction and Their Applications

Small, Год журнала: 2023, Номер 19(45)

Опубликована: Июль 11, 2023

Abstract Compared with the traditional electrolysis of water to produce hydrogen, urea‐assisted hydrogen has significant advantages and received extensive attention from researchers. Unfortunately, urea oxidation reaction (UOR) involves a complex six‐electron transfer process leading high overpotential, which forces researchers develop high‐performance UOR catalysts drive development splitting. Based on mechanism literature research, this review summarizes strategies for preparing highly efficient catalysts. First, is introduced characteristics excellent are pointed out. Aiming at this, following modulation proposed improve catalytic performance based summarizing various literature: 1) Accelerating active phase formation reduce initial potential; 2) Creating double sites trigger new mechanism; 3) adsorption promoting C─N bond cleavage ensure effective conduct UOR; 4) Promoting desorption CO 2 stability prevent catalyst poisoning; 5) electron overcome inherent slow dynamics 6) Increasing or surface area. Then, application in electrochemical devices summarized. Finally, current deficiencies future directions discussed.

Язык: Английский

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Accelerating the generation of NiOOH by in-situ surface phosphating nickel sulfide for promoting the proton-coupled electron transfer kinetics of urea electrolysis

Chemical Engineering Journal, Год журнала: 2024, Номер 483, С. 149264 - 149264

Опубликована: Фев. 3, 2024

Язык: Английский

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Ultrafine Homologous Ni₂P–Co₂P Heterostructures via Space‐Confined Topological Transformation for Superior Urea Electrolysis

Advanced Functional Materials, Год журнала: 2023, Номер 33(42)

Опубликована: Июнь 21, 2023

Abstract Constructing effective electrocatalysts based on ultrafine heterostructures is a promising strategy for boosting catalytic performance by exposing active sites and increasing specific surface area. However, the fabrication of catalytically with elaborate architectures still poorly developed owing to synthetic challenges, intrinsic mechanism heterogeneous interfaces remains unclear because insufficient evidence regarding real sites. In this study, homologous Ni 2 P–Co P (Ni P/C) are created using topological transformation from Ni–Co layered double hydroxide/carbon (Ni–Co LDH/C) interconnected structure in single nanosheet. When employed as catalysts urea oxidation reaction (UOR), P/C exhibit superior activity stability, attributed optimized geometric electronic structures Specifically, it takes an ultralow potential 1.27 V reach current density 10 mA cm −2 small Tafel slope 28.71 mV dec −1 . The operando analyses calculation results reveal that cobalt incorporation can reduce generation reconstructive species optimize absorption/desorption energy intermediates. Overall, study proposes efficient cost‐effective UOR electrocatalyst offers new high‐performance heterostructure design widespread application.

Язык: Английский

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Constructing CoNi-LDH/Fe MOF/NF Heterostructure Catalyst for Energy-Efficient OER and UOR at High Current Density

ACS Applied Materials & Interfaces, Год журнала: 2024, Номер 16(12), С. 14742 - 14749

Опубликована: Март 14, 2024

The sluggish kinetics of the oxygen evolution reaction (OER) always results in a high overpotential at anode water electrolysis and an excessive electric energy consumption, which has been major obstacle for hydrogen production through electrolysis. In this study, we present CoNi-LDH/Fe MOF/NF heterostructure catalyst with nanoneedle array morphology OER. 1.0 M KOH solution, only required overpotentials 275 305 mV to achieve current densities 500 1000 mA/cm2 OER, respectively. catalytic activities are much higher than those reference single-component CoNi-LDH/NF Fe catalysts. improved performance can be ascribed synergistic effect CoNi-LDH MOF. particular, when anodic OER is replaced urea oxidation (UOR), relatively lower thermodynamic equilibrium potential expected reduce cell voltage, same reduced by 80 40 mV, voltage drive overall splitting (OUS) 1.55 V 100 Pt/C/NF||CoNi-LDH/Fe two-electrode electrolytic cell. This value 60 compared that (OWS). Our indicate reasonable construction significantly give rise electrocatalytic performance, using UOR replace OWS greatly consumption.

Язык: Английский

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