Regulating the complex environment accounting for the stability, selectivity, and activity of catalytic metal nanoparticle interfaces represents a challenge to heterogeneous catalyst design. Here we demonstrate the intrinsic performance enhancement of a composite material composed of gold nanoparticles (AuNPs) embedded in a bottom-up synthesized graphene nanoribbon (GNR) matrix for the electrocatalytic reduction of CO. Electrochemical studies reveal that the structural and electronic properties of the GNR composite matrix increase the AuNP electrochemically active surface area (ECSA), lower the requisite CO reduction overpotential by hundreds of millivolts (catalytic onset > -0.2 V versus reversible hydrogen electrode (RHE)), increase the Faraday efficiency (>90%), markedly improve stability (catalytic performance sustained over >24 h), and increase the total catalytic output (>100-fold improvement over traditional amorphous carbon AuNP supports). The inherent structural and electronic tunability of bottom-up synthesized GNR-AuNP composites affords an unrivaled degree of control over the catalytic environment, providing a means for such profound effects as shifting the rate-determining step in the electrocatalytic reduction of CO to CO, and thereby altering the electrocatalytic mechanism at the nanoparticle surface.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/jacs.6b12217 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Conventional versus Unconventional Oxygen Reduction Reaction Intermediates on Single Atom Catalysts.
ACS Appl Mater Interfaces
January 2025
Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/Martí i Franquès 1-11, Barcelona 08028, Spain.
The oxygen reduction reaction (ORR) stands as a pivotal process in electrochemistry, finding applications in various energy conversion technologies such as fuel cells, metal-air batteries, and chlor-alkali electrolyzers. Hereby, a comprehensive density functional theory (DFT) investigation is presented into the proposed conventional and unconventional ORR mechanisms using single-atom catalysts (SACs) supported on nitrogen-doped graphene (NG) as model systems. Several reaction intermediates have been identified that appear to be more stable than the ones postulated in the conventional mechanism, which follows the *OOH, *O, and *OH intermediates.
View Article and Find Full Text PDFElectrocatalytic Reduction of Nitrate to Ammonia in an Aqueous Environment Using Nanoporous N- and P-Enriched Carbonaceous Material.
Langmuir
January 2025
Functional Materials Laboratory, Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India.
Carbonization (Argon atmosphere, 900 °C, 2 h) of heteroatom-enriched pyridine-bridged inorganic-organic hybrid material (HPHM) resulted in the formation of a high specific surface area (SA of 1080 m g) carbonaceous material designated as HPHMC900. The HPHMC900 serves as an effective electrocatalyst for the reduction of nitrate in an aqueous environment to ammonia (NORR). Importantly, HPHMC900 demonstrated fast kinetics for the NORR with a low Tafel slope of 70 mV decade.
View Article and Find Full Text PDFMain-Group Sn Single Atoms on MoS for Selective Nitrite Electroreduction to Ammonia.
ACS Appl Mater Interfaces
January 2025
School of Materials Science and Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China.
Electrocatalytic NO-to-NH reduction (NORR) offers an attractive way to remedy polluted NO and produce value-added NH. In this study, main-group Sn single atoms anchored on S-vacancy-rich MoS (Sn/MoS) are explored as a highly selective NORR catalyst. Combined theoretical computations and in situ spectroscopic measurements reveal that the isolated Sn sites of Sn/MoS can not only promote NO-to-NH activation and hydrogenation but also favor NH desorption and restrict H adsorption, thus enabling a highly selective NORR for NH synthesis.
View Article and Find Full Text PDFRevealing the Potential-Dependent Rate-Determining Step of Oxygen Reduction Reaction on Single-Atom Catalysts.
J Am Chem Soc
January 2025
Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
Single-atom catalysts (SACs) have attracted widespread attention due to their potential to replace platinum-based catalysts in achieving efficient oxygen reduction reaction (ORR), yet the rational optimization of SACs remains challenging due to their elusive reaction mechanisms. Herein, by employing ab initio molecular dynamics simulations and a thermodynamic integration method, we have constructed the potential-dependent free energetics of ORR on a single iron atom catalyst dispersed on nitrogen-doped graphene (Fe-N/C) and further integrated these parameters into a microkinetic model. We demonstrate that the rate-determining step (RDS) of the ORR on SACs is potential-dependent rather than invariant within the operative potential range.
View Article and Find Full Text PDFIn Situ Spectroscopic Probing of the Hydroxylamine Pathway of Electrocatalytic Nitrate Reduction on Iron-Oxy-Hydroxide.
Small
January 2025
Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, Delhi, 110016, India.
Crystalline γ-FeO(OH) dominantly possessing ─OH terminals (𝛾-FeO(OH)), polycrystalline γ-FeO(OH) containing multiple ─O, ─OH, and Fe terminals (𝛾-FeO(OH)), and α-FeO majorly containing ─O surface terminals are used as electrocatalysts to study the effect of surface terminals on electrocatalytic nitrate reduction reaction (eNORR) selectivity and stabilization of reaction intermediates. Brunauer-Emmett-Teller analysis and electrochemically determined surface area suggest a high active surface area of 117.79 m g (ECSA: 0.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!