Ultra-small highly fluorescent zinc-based metal organic framework nanodots for ratiometric visual sensing of tetracycline based on aggregation induced emission

Talanta, Journal Year: 2022, Volume and Issue: 254, P. 124178 - 124178

Published: Dec. 10, 2022

Language: Английский

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Non-Calcined Layer-Pillared Mn_0.5Zn_0.5 Bimetallic–Organic Framework as a Promising Electrocatalyst for Oxygen Evolution Reaction

Inorganic Chemistry, Journal Year: 2022, Volume and Issue: 61(25), P. 9514 - 9522

Published: June 14, 2022

Electrocatalytic generation of oxygen is great significance for sustainable, clean, and efficient energy production. Multiple electron transfer in evolution reaction (OER) its slow kinetics represent a serious hedge water splitting, requiring the design development advanced electrocatalysts with porous structures, high surface areas, abundant electroactive sites, low overpotentials. These requisites are common metal-organic frameworks (MOFs) derived materials that promising OER. The present work reports on synthesis full characterization heteroleptic 3D MOF, [Zn2(μ4-odba)2(μ-bpdh)]n·nDMF (Zn-MUM-1), assembled from 4,4'-oxydibenzoic acid 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (bpdh). Besides, series heterometallic MnZn-MUM-1 (abbreviated as Mn0.5Zn0.5-MUM-1, Mn0.66Zn0.33-MUM-1, Mn0.33Zn0.66-MUM-1) was also prepared, characterized, used fabrication working electrodes based Ni foam (NF), followed by their exploration noble-metal-free robust stable do not require pyrolysis or calcination while exhibiting better electrocatalytic performance than parent Zn-MUM-1/NF electrode. experimental results show Mn0.5Zn0.5-MUM-1/NF electrocatalyst features best OER activity overpotential (253 mV at 10 mA cm-2) Tafel slope (73 dec-1) well significant stability after 72 h 6000 cycles. excellent explained synergic effect two different metals Mn-Zn MOF improved charge ion transfer, conductivity, characteristics. study thus widens application MOFs prospective highly

Language: Английский

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Visual monitoring of silver ions and cysteine using bi-ligand Eu-based metal organic framework as a reference signal: Color tonality

Microchemical Journal, Journal Year: 2022, Volume and Issue: 181, P. 107721 - 107721

Published: June 22, 2022

Language: Английский

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Recent progress of transition metal-based bifunctional electrocatalysts for rechargeable zinc–air battery application

Current Opinion in Electrochemistry, Journal Year: 2023, Volume and Issue: 38, P. 101229 - 101229

Published: Feb. 4, 2023

Language: Английский

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Constructing Nitrogen‐Doped Carbon Hierarchy Structure Derived from Metal‐Organic Framework as High‐Performance ORR Cathode Material for Zn‐Air Battery

Small, Journal Year: 2023, Volume and Issue: 20(3)

Published: Sept. 10, 2023

Abstract The development of efficient and low‐cost catalysts for cathodic oxygen reduction reaction (ORR) in Zn‐air battery (ZAB) is a key factor reducing costs achieving industrialization. Here, novel segregated CoNiPt alloy embedded N‐doped porous carbon with nanoflowers (NFs)‐like hierarchy structure synthesized through pyrolyzing Hofmann‐type metal‐organic frameworks (MOFs). unique hierarchical NFs exposes more active sites facilitates the transportation intermediates, thus accelerating kinetics. Impressively, resulting 15% CoNiPt@C catalyst exhibits outstanding alkaline ORR activity half‐wave potential 0.93 V, its mass 7.5 times higher than that commercial Pt/C catalyst, surpassing state‐of‐the‐art noble metal‐based catalysts. Furthermore, assembled CoNiPt@C+RuO2 ZAB demonstrates maximum power density 172 mW cm −2 , which superior to Pt/C+RuO2 ZAB. Experimental results reveal intrinsic attributed synergistic interaction between defects pyrrolic/graphitic N species, optimizes adsorption energy intermediate species process greatly enhances catalytic activity. This work provides practical feasible strategy synthesizing cost‐effective by optimizing electronic MOF‐derived

Language: Английский

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Modulation Strategies for the Preparation of High‐Performance Catalysts for Urea Oxidation Reaction and Their Applications

Small, Journal Year: 2023, Volume and Issue: 19(45)

Published: July 11, 2023

Abstract Compared with the traditional electrolysis of water to produce hydrogen, urea‐assisted hydrogen has significant advantages and received extensive attention from researchers. Unfortunately, urea oxidation reaction (UOR) involves a complex six‐electron transfer process leading high overpotential, which forces researchers develop high‐performance UOR catalysts drive development splitting. Based on mechanism literature research, this review summarizes strategies for preparing highly efficient catalysts. First, is introduced characteristics excellent are pointed out. Aiming at this, following modulation proposed improve catalytic performance based summarizing various literature: 1) Accelerating active phase formation reduce initial potential; 2) Creating double sites trigger new mechanism; 3) adsorption promoting C─N bond cleavage ensure effective conduct UOR; 4) Promoting desorption CO 2 stability prevent catalyst poisoning; 5) electron overcome inherent slow dynamics 6) Increasing or surface area. Then, application in electrochemical devices summarized. Finally, current deficiencies future directions discussed.

Language: Английский

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Regulating the Spin‐State of Rare‐Earth Ce Single Atom Catalyst for Boosted Oxygen Reduction in Neutral Medium

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(47)

Published: July 16, 2023

Abstract The development of neutral zinc–air batteries (ZABs) is long been impeded by the sluggish oxygen reduction reaction (ORR) derived from insufficient O 2 activation and OH* blocking effect. Herein, synthesis a series rare‐earth Ce single‐atom catalysts (CeNCs) reported with enhanced spin‐state for boosting ORR. Experimental analysis theoretical calculations indicate that unique local coordination/geometric structure reshapes electronic configuration sites to achieve transition 4d 10 4f 1 8 3 . high‐spin active accelerate unpaired f electrons occupy anti‐π orbitals generate suitable binding strength intermediates. In conditions, CeNC‐40 exhibits excellent ORR performance half‐wave potentials 0.78 V negligible decay after 000 cycles. Additionally, self‐breathing ZABs based on demonstrates peak power density 81 mW cm −2 impressive long‐cycle stability (>1 600 cycles) at mA This work presents an effective strategy developing address challenges ZABs.

Language: Английский

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Optimizing Fe‐3d Electron Delocalization by Asymmetric Fe–Cu Diatomic Configurations for Efficient Anion Exchange Membrane Fuel Cells

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(46)

Published: Oct. 27, 2023

Abstract Precisely designing asymmetric diatomic configurations and studying their electronic regulation effect for improving the oxygen reduction reaction (ORR) performance are important anion exchange membrane fuel cells (AEMFCs). Here, a Fe, Cu co‐doped 2D crystalline IISERP‐MOF27 nanosheet derived FeN 3 O‐CuN 4 site nanocatalyst (named as FeCu‐NC) is synthesized cathodes of AEMFCs. Thanks to optimal structure in FeCu‐NC catalyst, it shows enhanced half‐wave potential (0.910 V), turnover frequency (0.165e s −1 ), decreased activation energy (19.96 kJ mol ) KOH. The FeCu‐NC‐based AEMFC achieves extremely high kinetic current (0.138 A cm −2 at 0.9 V) rated power density (1.09 W surpassing best‐reported transition metal‐based cathodes. Density functional theory calculations further demonstrate that Cu‐N can break localization Fe‐3d orbitals, accelerate electron transport, optimize OH adsorption, thus facilitating ORR process.

Language: Английский

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Engineering Molecular Heterostructured Catalyst for Oxygen Reduction Reaction

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(39), P. 21273 - 21283

Published: Sept. 20, 2023

Introducing a second metal species into atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts to construct diatomic sites (DASs) is an effective strategy elevate their activities and stabilities. However, the common pyrolysis-based method usually leads substantial uncertainty for formation of DASs, precise identification resulting DASs also rather difficult. In this regard, we developed two-step specific-adsorption (pyrolysis-free) constructed DAS catalyst featuring FeCo "molecular heterostructures" (FeCo-MHs). order rule out possibility two apparently neighboring (in electron microscopy image) Fe/Co atoms being respectively on top/bottom surfaces carbon support thus forming "false" MHs, conducted in situ rotation (by 8°, far above critical angle 5.3°) directly identified individual FeCo-MHs. The FeCo-MHs could modulate magnetic moments centers increase ratio low-spin Fe(II)-N4 moiety; intrinsic activity be optimized at apex volcano-plot (a relationship as function metal-phthalocyanine complexes catalytic activities). displays exceptional ORR (E1/2 = 0.95 V) used high-performance cathodes hydroxide exchange membrane fuel cells zinc-air batteries.

Language: Английский

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Recent advances in adsorption of environmental pollutants using metal–organic frameworks-based hydrogels

International Journal of Biological Macromolecules, Journal Year: 2023, Volume and Issue: 231, P. 123333 - 123333

Published: Jan. 19, 2023

Language: Английский

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