Engineering Water Molecules Activation Center on Multisite Electrocatalysts for Enhanced CO₂ Methanation

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(28), P. 12807 - 12815

Published: July 5, 2022

The renewable energy-powered electrolytic reduction of carbon dioxide (CO2) to methane (CH4) using water as a reaction medium is one the most promising paths store intermittent energy and address global sustainability problems. However, role in electrolyte often overlooked. In particular, slow dissociation kinetics limits proton-feeding rate, which severely damages selectivity activity methanation process involving multiple electrons protons transfer. Here, we present novel tandem catalyst comprising Ir single-atom (Ir1)-doped hybrid Cu3N/Cu2O multisite that operates efficiently converting CO2 CH4. Experimental theoretical calculation results reveal Ir1 facilitates into proton feeds sites for *CO protonation pathway toward *CHO. displays high Faradaic efficiency 75% CH4 with current density 320 mA cm-2 flow cell. This work provides strategy rational design high-efficiency catalytic systems.

Language: Английский

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Atomic‐Level Regulation of Cobalt Single‐Atom Nanozymes: Engineering High‐Efficiency Catalase Mimics

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(19)

Published: March 6, 2023

Nanozymes aim to mimic the highly evolved active centers of natural enzymes. Despite progress in nanozyme engineering, their catalytic performance is much less favorable compared with This study shows that precise control over atomic configuration Co single-atom nanozymes (SAzymes) enables rational regulation catalase-like guided by theorical calculations. The constructed Co-N3 PS SAzyme exhibits an excellent activity and kinetics, exceeding representative controls Co-based SAzymes different configurations. Moreover, we developed ordered structure-oriented coordination design strategy for rationally engineering established a correlation between structure enzyme-like performance. work demonstrates efficient sites

Language: Английский

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Atomically Dispersed Au-Assisted C–C Coupling on Red Phosphorus for CO₂ Photoreduction to C₂H₆

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(48), P. 22075 - 22082

Published: Nov. 22, 2022

Single-atom catalysts have exhibited great potential in the photocatalytic conversion of CO2 to C2 products, but generation gaseous multi-carbon hydrocarbon products is still challenging. Previously, supports a single atom consist multiple elements, making C-C coupling difficult because coordination environment single-atom sites diversified and control. Here, we steer by implanting an Au on red phosphorus (Au1/RP), support with uniform structure composed element, lower electronegativity, better ability absorb CO2. The electron-rich atoms near can function as active for activation. effectively reduce energy barrier coupling, boosting reaction kinetics formation C2H6. Notably, C2H6 selectivity turnover frequency Au1/RP reach 96% 7.39 h-1 without sacrificial agent, respectively, which almost represents best photocatalyst chemical synthesis date. This research will provide new ideas design high-efficiency photocatalysts products.

Language: Английский

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Regulating the FeN₄ Moiety by Constructing Fe–Mo Dual-Metal Atom Sites for Efficient Electrochemical Oxygen Reduction

Nano Letters, Journal Year: 2022, Volume and Issue: 22(23), P. 9507 - 9515

Published: Nov. 15, 2022

An Fe–N–C catalyst with an FeN4 active moiety has gained ever-increasing attention for the oxygen reduction reaction (ORR); however, catalytic performance is sluggish in acidic solutions and regulation still a challenge. Herein, Fe–Mo dual-metal sites were constructed to tune ORR activity of mononuclear Fe site embedded porous nitrogen-doped carbon. The cracking O–O bonds much more facile on atomic pair due preferred bridge-cis adsorption model molecules. downshift d band center when Mo atom introduced FeNx configuration optimizes absorption–desorption behavior intermediates FeMoN6 moiety, thus boosting performance. construction regulate catalytically paves way electrocatalytic other similar non-precious-metal catalysts.

Language: Английский

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Sb2S3-templated synthesis of sulfur-doped Sb-N-C with hierarchical architecture and high metal loading for H2O2 electrosynthesis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Jan. 23, 2023

Abstract Selective two-electron (2e − ) oxygen reduction reaction (ORR) offers great opportunities for hydrogen peroxide (H 2 O electrosynthesis and its widespread employment depends on identifying cost-effective catalysts with high activity selectivity. Main-group metal nitrogen coordinated carbons (M-N-Cs) are promising but remain largely underexplored due to the low metal-atom density lack of understanding in structure-property correlation. Here, we report using a nanoarchitectured Sb S 3 template synthesize high-density (10.32 wt%) antimony (Sb) single atoms nitrogen- sulfur-codoped carbon nanofibers (Sb-NSCF), which exhibits both selectivity (97.2%) mass (114.9 A g −1 at 0.65 V) toward 2e ORR alkaline electrolyte. Further, when evaluated practical flow cell, Sb-NSCF shows production rate 7.46 mol catalyst h negligible loss 75-h continuous electrolysis. Density functional theory calculations demonstrate that coordination configuration dopants synergistically contribute enhanced Sb-N 4 moieties.

Language: Английский

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