Rapid Charge Transfer Endowed by Interfacial Ni‐O Bonding in S‐scheme Heterojunction for Efficient Photocatalytic H₂ and Imine Production

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(50)

Published: Nov. 1, 2023

Cooperative coupling of H2 evolution with oxidative organic synthesis is promising in avoiding the use sacrificial agents and producing hydrogen energy value-added chemicals simultaneously. Nonetheless, photocatalytic activity obstructed by sluggish electron-hole separation limited redox potentials. Herein, Ni-doped Zn0.2 Cd0.8 S quantum dots are chosen after screening DFT simulation to couple TiO2 microspheres, forming a step-scheme heterojunction. The configuration tunes highly active site for augmented evolution, interfacial Ni-O bonds provide fast channels at atomic level lower barrier charge transfer. Also, calculations reveal an enhanced built-in electric field heterojunction superior migration separation. Kinetic analysis femtosecond transient absorption spectra demonstrates that expedited electrons first transfer Ni2+ then sites. Therefore, designed catalyst delivers drastically elevated yield (4.55 mmol g-1 h-1 ) N-benzylidenebenzylamine production rate (3.35 ). This work provides atomic-scale insights into coordinated modulation sites fields ameliorative performance.

Language: Английский

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Intermetallic Nanocrystals for Fuel-Cells-Based Electrocatalysis

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(22), P. 12507 - 12593

Published: Nov. 1, 2023

Electrocatalysis underpins the renewable electrochemical conversions for sustainability, which further replies on metallic nanocrystals as vital electrocatalysts. Intermetallic have been known to show distinct properties compared their disordered counterparts, and long explored functional improvements. Tremendous progresses made in past few years, with notable trend of more precise engineering down an atomic level investigation transferring into practical membrane electrode assembly (MEA), motivates this timely review. After addressing basic thermodynamic kinetic fundamentals, we discuss classic latest synthetic strategies that enable not only formation intermetallic phase but also rational control other catalysis-determinant structural parameters, such size morphology. We demonstrate emerging nanomaterials potentially advancement energy electrocatalysis. Then, state-of-the-art characterizations representative electrocatalysts emphasis oxygen reduction reaction evaluated a MEA setup. summarize review by laying out existing challenges offering perspective future research directions toward practicing conversions.

Language: Английский

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Optimizing Pt-Based Alloy Electrocatalysts for Improved Hydrogen Evolution Performance in Alkaline Electrolytes: A Comprehensive Review

ACS Nano, Journal Year: 2023, Volume and Issue: 17(21), P. 20804 - 20824

Published: Nov. 3, 2023

The splitting of water through electrocatalysis offers a sustainable method for the production hydrogen. In alkaline electrolytes, lack protons forces dissociation to occur before hydrogen evolution reaction (HER). While pure Pt is gold standard electrocatalyst in acidic since 5d orbital nearly fully occupied, when it overlaps with molecular water, generates Pauli repulsion. As result, formation Pt–H* bond an environment difficult, which slows HER and negates benefits using catalyst. To overcome this limitation, can be alloyed transition metals, such as Fe, Co, Ni. This approach has potential not only enhance performance but also increase dispersion decrease its usage, thus overall improving catalyst's cost-effectiveness. excellent adsorption ability metals contributes generation proton-rich local near Pt-based alloy that promotes HER. Significant progress been achieved comprehending mechanism manipulation structure composition electrocatalysts based on alloy. objective review analyze condense latest developments It focuses modified alloys clarifies design principles catalytic catalysts from both experimental theoretical perspective. highlights some difficulties encountered during opportunities increasing performance. Finally, guidance development more efficient provided.

Language: Английский

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Multi‐d Electron Synergy in LaNi_1‐xCo_xRu Intermetallics Boosts Electrocatalytic Hydrogen Evolution

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(1)

Published: Nov. 21, 2023

Despite the fact that d-band center theory links d electron structure of transition metals to their catalytic activity, it is yet unknown how synergistic effect multi-d electrons impacts performance. Herein, novel LaNi1-x Cox Ru intermetallics containing 5d, 4d, and 3d were prepared. In these compounds, 5d orbital La transfers 4d Ru, which provides adsorption sites for H*. The orbitals Ni Co interact with generate an anisotropic distribution, facilitates desorption OH*. ensures efficient activity. optimized LaNi0.5 Co0.5 has overpotential 43mV at 10 mA cm-2 alkaline electrocatalytic hydrogen evolution reaction. Beyond offering a variety new electrocatalysts, this work reveals synergy in promoting

Language: Английский

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Bifunctional CdS/COF S-scheme photocatalyst for enhanced H2 evolution and organic synthesis

Chemical Engineering Journal, Journal Year: 2023, Volume and Issue: 476, P. 146818 - 146818

Published: Oct. 20, 2023

It is an efficient strategy to construct photocatalysts by integrating the advantages of inorganic semiconductors and covalent organic frameworks (COFs) for H2 generation along with simultaneous oxidation. Herein, inorganic/organic CdS/COF (denoted as TpBD) 2D heterostructure fabricated electrostatic self-assembly method. The ultrathin structure can reduce charge transfer distance, enhance light absorption, multiply reaction sites while S-scheme heterojunction improves separation efficiency. composite acquires outstanding photocatalytic activity 15.1 mmol/g/h, simultaneously convert cheap ascorbic acid value-added 2,3-diketo-L-gulonic acid. Hall effect test elucidates dynamics carrier migration. electron paramagnetic resonance analysis, photo-irradiated Kelvin probe force microscopy, femtosecond transient absorption spectroscopy, theoretical calculation, in-situ irradiation X-ray photoelectron spectroscopy measurements confirm superiority transfer. This research presents new inspiration develop hydrogen production green chemical production.

Language: Английский

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Alleviating OH Blockage on the Catalyst Surface by the Puncture Effect of Single-Atom Sites to Boost Alkaline Water Electrolysis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(7), P. 4883 - 4891

Published: Feb. 7, 2024

Nonprecious transition metal catalysts have emerged as the preferred choice for industrial alkaline water electrolysis due to their cost-effectiveness. However, overstrong binding energy adsorbed OH often results in blockage of active sites, particularly cathodic hydrogen evolution reaction. Herein, we found that single-atom sites exhibit a puncture effect effectively alleviate blockades, thereby significantly enhancing reaction (HER) performance. Typically, after anchoring single Ru atoms onto tungsten carbides, overpotential at 10 mA·cm–2 is reduced by more than 130 mV (159 vs 21 mV). Also, mass activity increased 16-fold over commercial Pt/C (MA100 = 17.3 A·mgRu–1 1.1 A·mgPt–1, Pt/C). More importantly, such electrocatalyst-based anion-exchange membrane electrolyzers can an ultralow potential (1.79 Vcell) and high stability current density 1.0 A·cm–2. Density functional theory (DFT) calculations reveal isolated could weaken surrounding local energy, thus puncturing constructing bifunctional interfaces between support accelerate dissociation. Our findings generality other (such Mo) contribute advancement industrial-scale electrolysis.

Language: Английский

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ZnIn2S4/MOF S-scheme photocatalyst for H2 production and its femtosecond transient absorption mechanism

Journal of Material Science and Technology, Journal Year: 2024, Volume and Issue: 197, P. 183 - 193

Published: March 8, 2024

Language: Английский

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Relay Catalysis of Fe and Co with Multi‐Active Sites for Specialized Division of Labor in Electrocatalytic Nitrate Reduction Reaction

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: April 8, 2024

Abstract Electrocatalytic nitrate reduction reaction (NO 3 RR) driven by renewable energy is a promising technology for the removal of nitrate‐containing wastewater. However, sluggish kinetics resulted from complex proton‐coupled electron transfer and various intermediates remain key barriers large‐scale application NO RR. Herein, tactic reported to raise rate RR increase selectivity N 2 using bimetal catalyst: Co inclined act on steps needed in process, rate‐determining step (RDS: *NO , asterisk means intermediates) subsequent *N hydrogenation as well Fe exhibits efficient activity selectivity‐ determining (SDS: then ) via relay catalysis mechanism. A efficiency 78.5% an ultra‐long cycle stability 60 cycles (12 h per cycle) are achieved FeCo alloy confined with nitrogen‐doped porous carbon nanofibers (FeCo‐NPCNFs). DFT calculations unveil that introduction active site not only regulates d‐band center alloy, optimizes adsorption intermediates, but also has strong capacity supply hydrogen species. Clearly, this study elucidates effects bimetallic performance electrocatalytic offers avenues designing Fe‐based catalysts realize nitrogen‐neutral cycle.

Language: Английский

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High-entropy L12-Pt(FeCoNiCuZn)3 intermetallics for ultrastable oxygen reduction reaction

Journal of Energy Chemistry, Journal Year: 2023, Volume and Issue: 86, P. 158 - 166

Published: Aug. 2, 2023

Language: Английский

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Activating lattice oxygen by a defect-engineered Fe₂O₃–CeO₂ nano-heterojunction for efficient electrochemical water oxidation

Energy & Environmental Science, Journal Year: 2024, Volume and Issue: 17(14), P. 5260 - 5272

Published: Jan. 1, 2024

Self-supporting Fe 2 O 3 –CeO nano-heterojunction electrodes with rich oxygen vacancies present high catalytic performance for evolution reaction, where defect-engineering promotes the interfacial interaction and activates lattice oxygens.

Language: Английский

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