Cu1‐Fe Dual Sites for Superior Neutral Ammonia Electrosynthesis from Nitrate

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(31)

Published: May 21, 2024

Abstract The electrochemical nitrate reduction reaction (NO 3 RR) is able to convert − ) into reusable ammonia (NH ), offering a green treatment and resource utilization strategy of wastewater synthesis. conversion NO NH undergoes water dissociation generate active hydrogen atoms nitrogen‐containing intermediates hydrogenation tandemly. two relay processes compete for the same sites, especially under pH‐neutral condition, resulting in suboptimal efficiency selectivity electrosynthesis from . Herein, we constructed Cu 1 ‐Fe dual‐site catalyst by anchoring single on amorphous iron oxide shell nanoscale zero‐valent (nZVI) RR, achieving an impressive removal 94.8 % 99.2 neutral pH concentration 50 mg L −1 −N conditions, greatly surpassing performance nZVI counterpart. This superior can be attributed synergistic effect enhanced adsorption Fe sites strengthened activation single‐atom decreasing energy barrier rate‐determining step *NO‐to‐*NOH. work develops novel fabricating catalysts enhance , presents environmentally sustainable approach treatment.

Language: Английский

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Phosphorus–tungsten dual-doping boosts acidic overall seawater splitting performance over RuO_x nanocrystals

Journal of Materials Chemistry A, Journal Year: 2024, Volume and Issue: 12(41), P. 28023 - 28031

Published: Jan. 1, 2024

Dual-doped ruthenium-based nanocrystals were developed as efficient and stable electrocatalysts for acidic overall seawater splitting with superior activity durability.

Language: Английский

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Ultrathin High‐Entropy Fe‐Based Spinel Oxide Nanosheets with Metalloid Band Structures for Efficient Nitrate Reduction toward Ammonia

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(27)

Published: April 19, 2024

Abstract Spinel oxides with tunable chemical compositions have emerged as versatile electrocatalysts, however their performance is greatly limited by small surface area and low electron conductivity. Here, ultrathin high‐entropy Fe‐based spinel nanosheets are rationally designed (i.e., (Co 0.2 Ni Zn Mg Cu )Fe 2 O 4 ; denotes A 5 Fe ) in thickness of ≈4.3 nm large highly exposed active sites via a modified sol–gel method. Theoretic experimental results confirm that the bandgap significantly smaller than ordinary oxides, realizing transformation binary oxide from semiconductors to metalloids. As result, such manifest excellent for nitrate reduction reaction (NO 3 − RR) ammonia (NH ), NH yield rate ≈2.1 mmol h −1 cm −2 at −0.5 V versus Reversible hydrogen electrode, outperforming other spinel‐based electrocatalysts. Systematic mechanism investigations reveal NO RR mainly occurred on sites, introducing tetrahedral regulates adsorption strength N O‐related intermediates boosting RR. The above findings offer platform regulate enhance electrocatalytic oxides.

Language: Английский

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Engineering few-layer MoS2 and rGO heterostructure composites for high-performance supercapacitors

Advanced Composites and Hybrid Materials, Journal Year: 2025, Volume and Issue: 8(1)

Published: Jan. 7, 2025

Abstract Molybdenum disulfide (MoS 2 ) after the few-layer (FL) processing draws attention to its attractive characteristics, such as broadening interlayer spacing, increasing active sites, and promoting purity of metallic phase. Notwithstanding, poor stability easy aggregation FL-MoS limit potential for development in field electrochemistry. Herein, a nanocomposite between reduced graphene oxide (rGO) is successfully constructed via one-pot hydrothermal method. Furthermore, @rGO composite with stable structure obtained by regulating amount rGO. The excellent supercapacitor capacitances building heterostructure composites rGO are displayed, owing synergistic effects occurring heterostructure. optimal sample @rGO-2 possesses specific capacitance 346.1 F g −1 at 1 A rate ability 57.2%. Moreover, remains 99.1% 10,000 cyclic charges discharges. More importantly, theoretical calculations confirm source extra raise conductivity @rGO. Also, @rGO-2//AC flexible asymmetric device fabricated, which presents superior energy density power 84.31 µWh cm −2 700 µW , 51.42 3500 . This work verifies storage electrochemical application.

Language: Английский

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Highly Efficient Bifunctional NiFe-MOF Array Electrode for Nitrate Reduction to Ammonia and Oxygen Evolution Reactions

ACS Sustainable Chemistry & Engineering, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 16, 2025

Electrocatalytically converting nitrates in sewage to ammonia, which can not only achieve the purpose of eliminating but also obtaining valuable is an effective supplement traditional Haber–Bosch process. Although significant progress has been made cathodic catalyst design, overall ammonia electrolysis from nitrate reduction still restricted by anodic oxygen evolution heavily relying on noble-based catalysts. Herein, a bimetallic NiFe-MOF nanosheet array electrode fabricated and serves as efficient bifunctional for reactions. The introduction Fe Ni-MOF facilitates formation structure with higher electrochemical active surface area, well provides synergetic NiFe sites. reaches greatly enhanced yield rate 0.94 mmol cm–2 h–1 Faradaic efficiency 90.8% at cathode −0.6 V versus reversible hydrogen electrode, reaction declined overpotential 424 mV 50 mA cm–2. As electrocatalysis, performance comparable that using Pt mesh counter electrode.

Language: Английский

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Copper–Nickel Oxide Nanosheets with Atomic Thickness for High‐Efficiency Sulfur Ion Electrooxidation Assisted Nitrate Electroreduction to Ammonia

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(48)

Published: Aug. 16, 2024

Abstract The nitrate electroreduction reaction (NO 3 RR) offers an eco‐friendly alternative to the Haber–Bosch technology for ammonia (NH ) synthesis. However, complex process and diverse products make efficient NH synthesis challenging. Therefore, rational design preparation of highly electrocatalysts are crucial NO RR. Herein, ultrathin copper‐nickel oxide (Cu‐NiO) nanosheets (Cu‐NiO UTNSs) synthesized via cyanogel‐NaBH 4 hydrolysis‐reduction method, which applied cathodic RR ‐assisted with anodic sulfur ion (S 2− oxidation (SOR) in electrolyzer. nanosheet structure, interaction between NiO Cu, formation oxygen vacancy contribute generating rich active sites, regulating electronic improving substance adsorption. Thus, Cu‐NiO UTNSs exhibit excellent electrocatalytic performance SOR. As a bifunctional UTNSs||Cu‐NiO electrolyzer, it can reach 10 mA cm −1 at only 0.1 V − ‐to‐NH conversion cathode S ‐to‐S 8 anode. This work provides promising approach producing value‐added chemicals low electrolysis voltage strategy pollutant treatment.

Language: Английский

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Nanoflower‐Like CuPd/CuO Heterostructure for an Energy‐Output Electrocatalytic System Coupling Ammonia Electrosynthesis and Zinc‐Nitrate Battery

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 18, 2025

Abstract Electrochemical nitrate reduction reaction (NO 3 RR) can effectively alleviate pollution and simultaneously realize ammonia electrosynthesis at room temperature. However, it remains a significant challenge for NO RR to achieve high Faradic efficiency in full concentration range. Herein, nanoflower‐like copper‐palladium alloy/CuO heterostructure (CuPd/CuO@NF) is successfully fabricated by the hydrothermal synthesis of CuO nanoflowers subsequent formation CuPd alloy. The as‐obtained CuPd/CuO@NF exhibits remarkable electrochemical performance − ‐N range from 20 1400 ppm, especially with conversion rate 97.8% NH selectivity 99.3% 94.2% yield 1.37 mmol h −1 cm −2 ppm. In‐situ Fourier transform infrared spectroscopy Raman spectra reveal that first catalyzes 2 , which rapidly reduced forming *NH, *NH OH intermediates. Density functional theory calculations suggest NHO route thermodynamically favorable. When applied zinc‐nitrate battery, demonstrates maximum power density 53.7 mW 99.9% 94.4%. This work offers valuable insights into design novel electrocatalysts batteries.

Language: Английский

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Highly Stable Perovskite Oxides for Electrocatalytic Acidic NOx− Reduction Streamlining Ammonia Synthesis from Air

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 13, 2024

Electrochemical nitrogen oxide ions reduction reaction (NO

Language: Английский

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Tensile Strain and Interatomic Orbital Hybridization Effects Boost the Electrocatalytic Performance of Intermetallic Pd₃Pb Nanowires for Ethanol Electrooxidation^†

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: 42(21), P. 2633 - 2640

Published: July 10, 2024

Comprehensive Summary We present a strategy that effectively modulate the d‐band electronic structure of active center by strain effect and interatomic orbital hybridization. This efficiently promotes kinetic process ethanol oxidation reaction (EOR) in alkaline media. In intermetallic Pd 3 Pb nanowires, introduction not only causes lattice expansion but also achieves hybridization bonding with Pd. Such tensile can achieve co‐regulation Pd, which directly affects adsorption behavior intermediate on for EOR. Hence, nanowires demonstrate enhanced EOR activity anti‐poisoning ability against CO ads . Theoretical calculations show OH* low energy barrier oxidative dehydrogenation are keys to high stability nanowires.

Language: Английский

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Ultrathin Rh Nanosheets as a Catalyst for the Selective Hydrogenation of Phenol to Cyclohexanone

ACS Applied Nano Materials, Journal Year: 2025, Volume and Issue: 8(2), P. 1091 - 1099

Published: Jan. 2, 2025

The syntheses and catalytic application of two-dimensional (2D) metallic nanomaterials have attracted much attention due to their extraordinary physical, electronic, chemical, optical properties. Herein, well-defined large-size ultrathin Rh nanosheets with a thickness approximately 0.72 nm were successfully prepared by using one step solvothermal method at 180 °C for 4 h Rh(acac)3 as precursor, water solvent, EDTA·2Na stabilizer, HCHO both reducing agent shape-controlling agent. formation the was dependent upon well selective adsorption CO, which originated from decomposition during reaction process, on (111) facets nucleus. as-synthesized exhibited excellent activity high selectivity cyclohexanone in hydrogenation phenol. 100% conversion phenol 79.74% achieved over 0.5 MPa H2 pressure room temperature within 1.5 h. These results provide synthesis strategy precious metal applications.

Language: Английский

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