Tip‐like Fe−N₄ Sites Induced Surface Microenvironments Regulation Boosts the Oxygen Reduction Reaction

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(11)

Опубликована: Янв. 15, 2024

Abstract Single atom catalysts with defined local structures and favorable surface microenvironments are significant for overcoming slow kinetics accelerating O 2 electroreduction. Here, enriched tip‐like FeN 4 sites (T−Fe SAC) on spherical carbon surfaces were developed to investigate the change in catalysis behavior. Finite element method (FEM) simulations, together experiments, indicate strong electric field of more denser interfacial water layer, thereby enhancing proton‐coupled electron transfer process. In situ spectroelectrochemical studies density functional theory (DFT) calculation results pathway transition sites, promoting dissociation O−O bond via side‐on adsorption model. The adsorbed OH* can be facilely released curved accelerate oxygen reduction reaction (ORR) kinetics. obtained T−Fe SAC nanoreactor exhibits excellent ORR activities ( E 1/2 =0.91 V vs. RHE) remarkable stability, exceeding those flat Pt/C. This work clarified in‐depth insights into origin catalytic activity held great promise industrial catalysis, electrochemical energy storage, many other fields.

Язык: Английский

---

Ambient Electrochemical Ammonia Synthesis: From Theoretical Guidance to Catalyst Design

Advanced Science, Год журнала: 2024, Номер 11(15)

Опубликована: Фев. 12, 2024

Abstract Ammonia, a vital component in the synthesis of fertilizers, plastics, and explosives, is traditionally produced via energy‐intensive environmentally detrimental Haber–Bosch process. Given its considerable energy consumption significant greenhouse gas emissions, there growing shift toward electrocatalytic ammonia as an eco‐friendly alternative. However, developing efficient electrocatalysts capable achieving high selectivity, Faraday efficiency, yield under ambient conditions remains challenge. This review delves into decades‐long research synthesis, highlighting evolution fundamental principles, theoretical descriptors, reaction mechanisms. An in‐depth analysis nitrogen reduction (NRR) nitrate (NitRR) provided, with focus on their electrocatalysts. Additionally, theories behind electrocatalyst design for are examined, including Gibbs free approach, Sabatier principle, d ‐band center theory, orbital spin states. The culminates comprehensive overview current challenges prospective future directions development NRR NitRR, paving way more sustainable methods production.

Язык: Английский

---

Substantial Impact of Spin State Evolution in OER/ORR Catalyzed by Fe–N–C

ACS Catalysis, Год журнала: 2024, Номер 14(9), С. 6816 - 6826

Опубликована: Апрель 18, 2024

The Fe-embedded N-doped graphene (Fe–N–C) is the most representative single atom catalyst (SAC) that has shown great potentiality in electrocatalysis, such as oxygen reduction reaction (ORR) and evolution (OER). However, active moiety of Fe–N–C still elusive due to contradictory experimental results. Moreover, early simulations mainly focus on thermodynamic potential adsorbates, while effect spin multiplicity receives little attention. To explore role we employ constant-potential density functional theory (DFT) systematically study structural high-spin (HS) intermediate-spin (IS) FeN4 site (marked by FeN4HS/IS) OER ORR processes. With consideration multiplicity, our simulation shows spontaneous oxidation from Fe(II)N4IS Fe(III)N4HS at U = 0.4 V versus SHE. Further indicates FeN4IS undergoes a sequential adsorption *OH *OOH along with increase, which leads state transition IS HS. According free energy analysis, FeN4HS*OOH confirmed be practical centers OER, FeN4HS*OH are assigned center low high overpotentials. predicted activity agrees situ X-ray absorption near-edge spectroscopy (XANES) 57Fe Mössbauer measurement Xiao et al. [Microporous Framework Induced Synthesis Single-Atom Dispersed Fe-NC Acidic Catalyst its In Situ Reduced Fe-N4 Active Site Identification Revealed X-Ray Absorption Spectroscopy. ACS Catal. 2018, 8, 2824–2832]. Based geometry orbital bond length Fe–N coordination number Fe found have significant impact d splitting thus induce turnover HS/IS stability OER/ORR intermediates. Our brings comprehensive insights into Fe–N–C, reveals significance electrocatalysis benefits further theoretical design SACs perspective effects.

Язык: Английский

---

Modeling Interfacial Dynamics on Single Atom Electrocatalysts: Explicit Solvation and Potential Dependence

Accounts of Chemical Research, Год журнала: 2024, Номер 57(2), С. 198 - 207

Опубликована: Янв. 3, 2024

ConspectusSingle atom electrocatalysts, with noble metal-free composition, maximal efficiency, and exceptional reactivity toward various energy environmental applications, have become a research hot spot in the recent decade. Their simplicity isolated nature of atomic structure their active site also made them an ideal model catalyst system for studying reaction mechanisms activity trends. However, state single sites during electrochemical reactions may not be as simple is usually assumed. To contrary, electrocatalysts been reported to under greater influence from interfacial dynamics, solvent electrolyte ions perpetually interacting electrified center applied electrode potential. These complexities render trends derived simplistic models dubious.In this Account, few popular electrocatalysis systems, we show how change potential induces nontrivial variation free profile elemental steps, demonstrate centers different electronic features can induce solvation structures at interface even same intermediate simplest reaction, discuss implication on kinetics thermodynamics better address selectivity We venture into more intriguing phenomena, such alternative pathways intermediates that are favored stabilized by polarization effects, long-range dynamics across region far beyond contact layer, dynamic activation or deactivation operation conditions. necessity including realistic aspects (explicit solvent, electrolyte, potential) correctly capture physics chemistry understand design principles fail they revised factors model. All these rich would remain hidden overlooked otherwise. believe complexity curse but blessing it enables deeper understanding finer control potential-dependent landscape reactions, which opens up new dimensions further optimization beyond. Limitations current methods challenges faced theoretical experimental communities discussed, along possible solutions awaiting development future.

Язык: Английский

---

From Single Metals to High‐Entropy Alloys: How Machine Learning Accelerates the Development of Metal Electrocatalysts

Advanced Functional Materials, Год журнала: 2024, Номер 34(34)

Опубликована: Апрель 25, 2024

Abstract The rapid advancement of high‐performance computing and artificial intelligence technology has opened up novel avenues for the development various metal electrocatalysts. In particular, dilute high‐entropy alloys have garnered significant attention owing to their unique electronic spatial structures, as well exceptional electrocatalytic performance. Commencing with exploration single‐atom alloy catalysts, latest advancements in machine learning (ML) techniques are presented efficient screening a broad spectrum spaces. Subsequently, review delves into prevailing trend research, focusing specifically on rare‐metal electrocatalysts, offers an overview progress outcomes achieved through application ML these domains. Finally, highlighted promising category electrocatalysts underscore importance potential applications addressing complex challenging research issues underscored.

Язык: Английский

---

Revealing the role of electrode potential micro-environments in single Mn atoms for carbon dioxide and oxygen electrolysis

Nano Research, Год журнала: 2024, Номер 17(9), С. 7957 - 7966

Опубликована: Июль 1, 2024

Язык: Английский

---

Insights into the Optimization of Catalytic Active Sites in Lithium–Sulfur Batteries

Accounts of Chemical Research, Год журнала: 2024, Номер 57(15), С. 2093 - 2104

Опубликована: Июнь 26, 2024

ConspectusLithium-sulfur batteries (LSBs), recognized for their high energy density and cost-effectiveness, offer significant potential advancement in storage. However, widespread deployment remains hindered by challenges such as sluggish reaction kinetics the shuttle effect of lithium polysulfides (LiPSs). By introduction catalytic materials, effective adsorption LiPSs, smooth surface migration behavior, significantly reduced conversion barriers are expected to be achieved, thereby sharpening electrochemical fundamentally addressing aforementioned challenges. driven practical application targets, demand higher loadings electrolyte parameters inevitably exacerbates burden on materials during service. Additionally, given that contribute negligible capacity, incorporation increases mass nonactive components reducing LSBs. A meticulous insight into lithium-sulfur reveals LiPSs is dominated active sites surfaces materials. These microregions provide necessary electron ion transport with efficacy quantity directly impacting efficiency. In light these considerations, strategic optimization emerges a paramount pathway toward promoting performance LSBs while concurrently mitigating unnecessary mass. Here, we outline three strategies developed our group optimize materials: (1) Augmenting customizing structural modulation precise dimensional control maximize exposure. Emphasis has been placed approaches material synthesis essence reactions achieving this strategy. (2) Regulating microenvironment integrating coordination refinement, long-range atomic interactions, metal-support other electronic regulation strategies, providing an elevation intrinsic performance. (3) Implementing self-cleaning mechanism counteract deactivation designing tandem adsorption-migration-transformation sulfur contained within molecular domain. Throughout process, mechanisms driving enhancement through site have prominently emphasized, which encompass aspects structure, composition, configuration expand comprehension Li-S chemistry. Subsequently, considerations demanding heightened attention future processes delineated, including situ evolution patterns resistance poisoning sites. It noteworthy similarity between catalysis chemistry traditional electrocatalytic processes, Account elucidates concept drawing insights from representative works own field electrocatalysis, relatively rare previous reviews The proposed uncovering introducing innovative ideas optimization, ultimately advancing stability

Язык: Английский

---

Enhancing CO2 photoreduction on Au@CdZnS@MnO2 hollow nanospheres via electron configuration modulation

Journal of Material Science and Technology, Год журнала: 2025, Номер unknown

Опубликована: Фев. 1, 2025

Язык: Английский

---

Spin polarization induced by atomic strain of MBene promotes the ·O2– production for groundwater disinfection

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 2, 2025

Язык: Английский

---

Ni and Co Active Site Transition and Competition in Fluorine‐Doped NiCo(OH)₂ LDH Electrocatalysts for Oxygen Evolution Reaction

Small, Год журнала: 2024, Номер 20(31)

Опубликована: Март 18, 2024

Abstract The oxygen evolution reaction (OER) performance of NiCo LDH electrocatalysts can be improved through fluorine doping. roles Ni and Co active sites in such catalysts remain ambiguous controversial. In addressing the issue, this study draws upon molecular orbital theory proposes center competitive mechanism between Co. doped F‐atoms directly impact valence state metal atoms or exert an indirect influence dehydrogenation, thereby modulating center. As are progressively aggregate, e g orbitals transition from 2 to 1 , subsequently 0 . corresponding elevates +2 +3, then +4, signifying initial increase followed by a subsequent decrease electrocatalytic performance. Furthermore, series F‐NiCo synthesized verify occupancy analysis, catalytic OER overpotentials 303, 243, 240, 246 mV at current density 10 mA cm −2 respectively, which coincides well with theoretical prediction. This investigation not only provides novel mechanistic insights into competition but also establishes foundation for design high‐performance catalysts.

Язык: Английский

---