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You searched for: Publication year rev 7980-2020 Remove constraint Publication year rev: 7980-2020 Subject term catalysts Remove constraint Subject term: catalysts
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1. (Arylimido)niobium(V)–Alkylidenes, Nb(CHSiMe₃)(NAr)[OC(CF₃)₃](PMe₃)₂, That Enable to Proceed Living Metathesis Polymerization of Internal Alkynes

Author:
Itsuki Izawa; Kotohiro Nomura
Source:
Macromolecules 2020 v.53 no.13 pp. 5266-5279
ISSN:
1520-5835
Subject:
alkynes; catalysts; niobium; polymerization
Abstract:
... Living polymerizations of internal alkynes (2-hexyne, 3-hexyne, 4-methyl-2-pentyne, and 1-phenyl-1-propyne) have been demonstrated at 50 °C by (arylimido)niobium(V)–alkylidene complex catalysts, Nb(CHSiMe₃)(NAr)[OC(CF₃)₃](PMe₃)₂ [Ar = 2,6-Me₂C₆H₃ (4a), 2-MeC₆H₄ (4c), and 2,6-Cl₂C₆H₃ (4d)], in the presence of PMe₃, which plays an essential role to proceed the living polymerization without certain c ...
DOI:
10.1021/acs.macromol.0c00874

2. (Fe,N-codoped carbon nanotube)/(Fe-based nanoparticle) nanohybrid derived from Fe-doped g-C3N4: A superior catalyst for oxygen reduction reaction

Author:
Yanpei Zhang; Ruibin Jiang; Zhongke Wang; Yanzhong Xue; Jie Sun; Yingjie Guo
Source:
Journal of colloid and interface science 2020 v.579 pp. 391-400
ISSN:
0021-9797
Subject:
batteries; carbon nanotubes; carbon nitride; carbonization; catalysts; catalytic activity; electrochemistry; fuel cells; iron; moieties; nanohybrids; nanoparticles
Abstract:
... Transition metal- and N-codoped carbon nanotubes (CNTs) have superior catalytic activity because the curling surface enhances the bonding ability of atoms within CNTs to other species. However, it is a great challenge to prepare CNTs with transition metal- and N-doped at high level during the growth of CNTs. Here, (Fe,N-codoped CNT)/(Fe-based nanoparticle) (Fe,N-CNT/FeNP) hybrid nanostructures are ...
DOI:
10.1016/j.jcis.2020.06.057

3. 2-Methylimidazole directed ambient synthesis of zinc-cobalt LDH nanosheets for efficient oxygen evolution reaction

Author:
Chunyu Qiu; Fuxian Cai; Yuan Wang; Yijun Liu; Qingxiang Wang; Chuan Zhao
Source:
Journal of colloid and interface science 2020 v.565 pp. 351-359
ISSN:
0021-9797
Subject:
ambient temperature; catalysts; catalytic activity; cobalt; electrochemistry; ethanol; glassy carbon electrode; green chemistry; microparticles; nanosheets; oxides; oxygen production; potassium hydroxide; sodium hydroxide; surface area; zinc
Abstract:
... It is a highly desired yet challenging task to replace rare and expensive noble metal catalysts with inexpensive and earth-abundant metal ones in electrochemical sustainable chemistry field. Herein, the bimetallic zinc-cobalt layered double hydroxide nanosheets (ZnCo-LDH NS) have been facilely synthesized using 2-methylimidazole as a bifunctional alkali source (OH⁻) and a morphological controlling ...
DOI:
10.1016/j.jcis.2019.12.070

4. 2D black phosphorus and tungsten trioxide heterojunction for enhancing photocatalytic performance in visible light

Author:
Qi Wang; Bihan Li; Ping Zhang; Wenming Zhang; Xiaoru Hu; Xiaochen Li
Source:
RSC advances 2020 v.10 no.46 pp. 27538-27551
ISSN:
2046-2069
Subject:
X-ray diffraction; X-ray photoelectron spectroscopy; catalysts; coprecipitation; energy; light; liquid chromatography; liquids; mass spectrometry; phosphorus; photocatalysis; photolysis; rhodamines; scanning electron microscopy; tungsten oxide; ultraviolet-visible spectroscopy
Abstract:
... A novel, efficient and stable 2D black phosphorus and tungsten trioxide heterojunction (WO₃–BPNs) was successfully synthesized using a combined hydrothermal, liquid phase exfoliating and co-precipitation method. The as-obtained WO₃–BPNs composite was characterized by using XRD, SEM, XPS, UV-vis, etc. The results showed that the bandgap energy of the WO₃–BPNs50 sample was 2.2 eV, which was lower th ...
DOI:
10.1039/d0ra05230b

5. 2D surface induced self-assembly of Pd nanocrystals into nanostrings for enhanced formic acid electrooxidation

Author:
Sheng Zhang; Rong Xia; Yaqiong Su; Yichao Zou; Chengyi Hu; Geping Yin; Emiel J. M. Hensen; Xinbin Ma; Yuehe Lin
Source:
Journal of materials chemistry A 2020 v.8 no.33 pp. 17128-17135
ISSN:
2050-7496
Subject:
adsorption; catalysts; density functional theory; formates; formic acid; graphene; graphene oxide; nanocrystals; nanoparticles; oxidation; palladium
Abstract:
... Two-dimensional (2D) graphene has been widely used as an ideal substrate for many functional materials. It is crucial to understand and control the growth of metal nanocrystals on the graphene surface. Herein we report a novel phenomenon that pre-synthesized palladium nanoparticles are spontaneously transformed into palladium nanostrings (Pd NSs) with nanoscale grain boundaries induced by the redu ...
DOI:
10.1039/d0ta06171a

6. 2nd generation biomass derived glucose conversion to 5-hydroxymethylfurfural and levulinic acid catalyzed by ionic liquid and transition metal sulfate: Elucidation of kinetics and mechanism

Author:
Komal Kumar; Shailesh Pathak; Sreedevi Upadhyayula
Source:
Journal of cleaner production 2020 v.256 pp. 120292
ISSN:
0959-6526
Subject:
activation energy; batch systems; biomass; catalysts; catalytic activity; glucose; humin; hydroxymethylfurfural; ionic liquids; kinetics; levulinic acid; models; nickel; reaction mechanisms; recycling; renewable energy sources; sulfates; synergism; temperature; wastes
Abstract:
... The conversion of 2ⁿᵈ generation biomass to 5-HMF and LA is a promising route for the production of key platform chemicals and renewable fuels. This work reports a clean synthesis of levulinic acid (LA) and 5-hydroxymethyl furfural (5-HMF) from waste biomass derived glucose in aqueous phase using –SO₃H functionalized ionic liquid (IL) catalyst [IL-SO₃H][Cl] and nickel sulfate (NiSO₄.6H₂O) co-catal ...
DOI:
10.1016/j.jclepro.2020.120292

7. 3D Rosa centifolia-like CeO2 encapsulated with N-doped carbon as an enhanced electrocatalyst for Zn-air batteries

Author:
Yumao Kang; Wei Wang; Jinmei Li; Yajun Mi; Hongyan Gong; Ziqiang Lei
Source:
Journal of colloid and interface science 2020 v.578 pp. 796-804
ISSN:
0021-9797
Subject:
Rosa; active sites; batteries; carbon; catalysts; catalytic activity; ceric oxide; electrochemistry; encapsulation; energy density; energy efficiency; oxygen; oxygen production; platinum
Abstract:
... Reasonable design and synthesis of high-efficiency rare earth oxides-based materials as alternatives to noble-metal catalysts are of great significance for oxygen electrocatalysis. Herein, we report three-dimension (3D) Rosa centifolia-like CeO₂ encapsulated with N-doped carbon (NC) composites (CeO₂@NC) for enhancing oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities. T ...
DOI:
10.1016/j.jcis.2020.06.040

8. 3D flower-like ZnFe-ZIF derived hierarchical Fe, N-Codoped carbon architecture for enhanced oxygen reduction in both alkaline and acidic media, and zinc-air battery performance

Author:
Zhiwei Zhang; Huihui Jin; Jiawei Zhu; Wenqiang Li; Chengtian Zhang; Jiahuan Zhao; Feng Luo; Zhigang Sun; Shichun Mu
Source:
Carbon 2020 v.161 pp. 502-509
ISSN:
0008-6223
Subject:
active sites; aqueous solutions; batteries; carbon; carbon nanotubes; catalysts; coordination polymers; electrochemistry; energy density; fuel cells; imidazole; iron; methanol; moieties; oxygen; platinum; pyrolysis
Abstract:
... Developing highly efficient and durable noble-metal-free electrocatalysts towards oxygen reduction reaction (ORR) is desperately urgent for realizing widespread application of fuel cells and metal-air batteries. Recently, great importance has been attached to metal-organic framework (MOF)-derived carbon-based materials due to the low cost and excellent performance. Herein, a novel zeolitic imidazo ...
DOI:
10.1016/j.carbon.2020.01.108

9. 3D freestanding flower-like nickel-cobalt layered double hydroxides enriched with oxygen vacancies as efficient electrocatalysts for water oxidation

Author:
Yihao Liu; Yingying Chen; Riyue Ge; Wenxian Li; Yuan Zhang; Lingyan Feng; Renchao Che
Source:
Sustainable materials and technologies 2020 v.25 pp. e00170
ISSN:
2214-9937
Subject:
catalysts; catalytic activity; durability; electrochemistry; energy conversion; hydroxides; nanosheets; oxidation; oxygen; oxygen production; surface area
Abstract:
... Economic, efficient, and stable layered double hydroxides (LDHs) based oxygen evolution reaction (OER) electrocatalysts are recognized as promising substitutions of precious catalysts. While LDHs composites suffer from low intrinsic activity, which slightly impedes their wide utilization in energy conversion. Here, we demonstrate a kind of three-dimensional (3D) freestanding flower-like NiCo-LDHs ...
DOI:
10.1016/j.susmat.2020.e00170

10. 3D-structured CuCo2S4 as an excellent Fenton-like catalyst under alkaline solution

Author:
Meilin He; Zhaodong Nan
Source:
Powder technology 2020 v.376 pp. 263-271
ISSN:
0032-5910
Subject:
catalysts; catalytic activity; cobalt; copper; electrical conductivity; hydrogen peroxide; hydroxyl radicals; metal ions; nanosheets; pH; sulfides; superoxide anion; synergism
Abstract:
... Synergistic effects among metal cations on the catalytic activity for the Fenton reaction are drawing much attention. Effects of pH of the solution on these synergistic effects have not been reported as far as we know. In the present study, 3D CuCo₂S₄ assembled by nanosheets was synthesized as a catalyst for the Fenton reaction. Compared with the most catalysts displayed high levels of the activit ...
DOI:
10.1016/j.powtec.2020.08.010

11. 6π-Electrocyclization in water: microwave-assisted synthesis of polyheterocyclic-fused quinoline-2-thiones

Author:
Xiao-Yun Li; Yan Liu; Xiao-Lan Chen; Xin-Yuan Lu; Xing-Xing Liang; Shan-Shan Zhu; Chuan-Wan Wei; Ling-Bo Qu; Bing Yu
Source:
Green chemistry 2020 v.22 no.14 pp. 4445-4449
ISSN:
1463-9270
Subject:
additives; carbon disulfide; catalysts; filtration; green chemistry; microwave treatment
Abstract:
... Microwave-assisted synthesis of polyheterocyclic-fused quinoline-2-thiones through the annulation of ortho-heteroaryl anilines and CS₂ was realized in water without using any catalysts and additives. The desired products were obtained in high yields through simple filtration. A remarkable E-factor of 0.45 and an EcoScale score of 85.5 were obtained. ...
DOI:
10.1039/c9gc04445k

12. A Bilayer Structure Composed of MgCo-MnO₂ Deposited on a Co(OH)₂ Film to Realize Selective Oxygen Evolution from Chloride-Containing Water

Author:
Takuya Okada; Hikaru Abe; Ai Murakami; Tomohito Shimizu; Kenta Fujii; Toru Wakabayashi; Masaharu Nakayama
Source:
Langmuir 2020 v.36 no.19 pp. 5227-5235
ISSN:
1520-5827
Subject:
active sites; catalysts; chlorides; chlorine; coatings; cobalt; density functional theory; electrolysis; glass electrodes; hydrolysis; ion exchange; ions; magnesium; manganese; manganese dioxide; nitrates; oxidation; oxygen; oxygen production; pH; permeability; quaternary ammonium compounds; seawater; sodium; tin
Abstract:
... A fluorine-doped tin oxide-coated glass electrode modified with a bilayer film of underlying α-Co(OH)₂ and overlying Mg-intercalated and Co-doped δ-type (layered) MnO₂ (MgCo-MnO₂) preferentially yielded oxygen with a Faradaic efficiency as high as 79% in the presence of chloride ions at high concentration (0.5 M). This noble metal-free electrode was fabricated by cathodic electrolysis of aqueous C ...
DOI:
10.1021/acs.langmuir.0c00547

13. A Bond-Energy-Integrated-Based Descriptor for High-Throughput Screening of Transition Metal Catalysts

Author:
Cong Xi; Chengqin Zou; Min Wang; Deyao Wu; Hui Liu; Cunku Dong; Xi-Wen Du
Source:
Journal of physical chemistry 2020 v.124 no.9 pp. 5241-5247
ISSN:
1932-7455
Subject:
adsorbents; adsorption; carbon dioxide; catalysts; copper; energy; geometry; gold; high-throughput screening methods; iridium; nickel; palladium; platinum; prediction; rhodium; screening; silver
Abstract:
... Developing a theoretical descriptor for chemisorption is of great importance on exploiting highly efficient catalysts. As yet, there still lacks a universal descriptor to accurately differentiate the chemisorption on diverse transition metals (TMs). Herein, we propose a bond-energy-integrated-based descriptor, which involves the electronic structure and geometric environment of the TMs simultaneou ...
DOI:
10.1021/acs.jpcc.9b11902

14. A B₂(OH)₄-Mediated Synthesis of 2-Substituted Indazolone and Its Application in a DNA-Encoded Library

Author:
Yapeng Bao; Zongfa Deng; Jing Feng; Weiwei Zhu; Jin Li; Jinqiao Wan; Guansai Liu
Source:
Organic letters 2020 v.22 no.16 pp. 6277-6282
ISSN:
1523-7052
Subject:
DNA; aromatic amines; bioactive compounds; catalysts; libraries; metals; methodology; wills
Abstract:
... Indazolone cores are among the most common structural components in medicinal chemistry and can be found in many biologically active molecules. In this report, a mild and efficient approach to 2-substituted indazolones via B₂(OH)₄-mediated reductive N–N bond formation is developed. This strategy features mild conditions, no request for a metal catalyst, and a wide scope for both aliphatic and arom ...
DOI:
10.1021/acs.orglett.0c02032

15. A DFT Study and Microkinetic Simulation in Propylene Oxidation on the “29” CuₓO/Cu(111) Surface

Author:
Tian-Tian Xiao; Rui-Shi Li; Gui-Chang Wang
Source:
Journal of physical chemistry 2020 v.124 no.12 pp. 6611-6623
ISSN:
1932-7455
Subject:
activation energy; catalysts; catalytic activity; copper; cuprous oxide; dehydrogenation; density functional theory; energy; epoxidation reactions; oxidants; oxidation; oxygen; physical chemistry; propylene; sustainable technology; value-added products
Abstract:
... The propylene epoxidation reaction in a rich variety of other industrially important catalytic processes was used for synthesis of many value-added products. As an attractive and environmentally friendly process for direct epoxidation of propylene by Cu-based catalysts, the active oxidation states of Cu (Cu⁰, Cu⁺, or Cu⁰/Cu⁺) in the epoxidation reaction were widely studied. Herein, “29” CuₓO/Cu(11 ...
DOI:
10.1021/acs.jpcc.9b11347

16. A Density Functional Theory Study of the Two-Dimensional Bis(iminothiolato)metal Monolayers as Efficient Electrocatalysts for Oxygen Reduction Reaction

Author:
Guanru Xing; Lin Cheng; Kai Li; Yan Gao; Hao Tang; Ying Wang; Zhijian Wu
Source:
Journal of physical chemistry 2020 v.124 no.14 pp. 7803-7811
ISSN:
1932-7455
Subject:
adsorption; catalysts; catalytic activity; cobalt; coordination polymers; copper; density functional theory; electrochemistry; energy; iridium; iron; manganese; nickel; palladium; platinum; rhodium; ruthenium
Abstract:
... In recent years, two-dimensional metal–organic frameworks (MOF)-derived heteroatom-doped carbon-based electrocatalysts have drawn extensive attention due to the superior catalytic activity for oxygen reduction reaction (ORR). In this work, the ORR catalytic activity of a series of bis(iminothiolato)metal (TMIT) (TM = Mn, Fe, Co, Ni, Cu, Ru, Rh, Pd, Ir, and Pt) monolayers has been investigated by u ...
DOI:
10.1021/acs.jpcc.9b11890

17. A Janus antimony sulfide catalyst for highly selective N₂ electroreduction

Author:
Haifeng Nan; Yaping Liu; Qingqing Li; Peng Shen; Ke Chu
Source:
Chemical communications 2020 v.56 no.71 pp. 10345-10348
ISSN:
1364-548X
Subject:
adsorption; antimony; catalysts; hybridization; hydrogen production; nanoflowers; nitrogen; protonation; sulfides
Abstract:
... The antimony sulfide Sb₂S₃ is firstly explored as a Janus catalyst for highly selective nitrogen reduction reaction (NRR). The developed Sb₂S₃ nanoflowers delivered an excellent faradaic efficiency of 24.1% and a high NH₃ yield of 33.4 μg h⁻¹ mg⁻¹ at −0.3 V. Theoretical calculations revealed that the high NRR selectivity of Sb₂S₃ originated from the Janus role of active Sb centers: on one hand, Sb ...
DOI:
10.1039/d0cc04764c

18. A Laser-Activated Membrane Introduction Mass Spectrometry Study of Proton Spillover Promoted Alkane Dehydrogenation

Author:
Ryan Yongtae Kim; Harry Rivera; Sara E. Evarts; José A. Rodríguez-Martínez; Richard R. Willis; Douglas B. Galloway; Falaah Falih; Michael J. McCall; S. Jackson Smith; Kyra Perz; Eugene S. Smotkin
Source:
Analytical chemistry 2020 v.92 no.19 pp. 13462-13469
ISSN:
1520-6882
Subject:
alkanes; analytical chemistry; carbon; catalysts; dehydrogenation; mass spectrometry; paper; silicone; surface area; toluene
Abstract:
... Operando high-throughput evaluation of heterogeneous catalysts by laser-activated membrane introduction mass spectrometry (LAMIMS) elucidates the Pt loading dependence of methylcyclohexane dehydrogenation on platinized γ-alumina beads. A CO₂ marking laser rapidly and sequentially heats catalyst beads positioned on a heat-dissipating carbon paper support that overlays a silicone membrane, separatin ...
DOI:
10.1021/acs.analchem.0c02886

19. A Liquid Chromatographic Analysis of Deferasirox in Human Breast Milk with Fluorimetric Detection

Author:
Cem Onal; Serife Evrim Kepekci Tekkeli; Ali Asram Sagiroglu
Source:
Chromatographia 2020 v.83 no.11 pp. 1329-1333
ISSN:
0009-5893
Subject:
breast milk; catalysts; coumarin; derivatization; fluorescence; fluorometry; high performance liquid chromatography; pH; particle size; reversed-phase liquid chromatography; standard deviation
Abstract:
... To determine deferasirox in human breast milk a novel, sensitive high-performance liquid chromatographic method with fluorescence detection has been developed. Precolumn derivatization process is applied to achieve fluorescent analyte using 4-bromomethyl-7-methoxy coumarin (BrMmC) as a reagent and dibenzo-18-crown-6-ether as catalyst. The method depends on reverse phase chromatography. C₁₈ column ...
DOI:
10.1007/s10337-020-03953-5

20. A Method for the Selective Quantification of Brønsted Acid Sites on External Surfaces and in Mesopores of Hierarchical Zeolites

Author:
Carolin Rieg; Zheng Li; Alan Kurtz; Maximilian Schmidt; Daniel Dittmann; Michael Benz; Michael Dyballa
Source:
Journal of physical chemistry 2020 v.125 no.1 pp. 515-525
ISSN:
1932-7455
Subject:
acidity; aluminum; catalysts; catalytic activity; nuclear magnetic resonance spectroscopy; physical chemistry; solvents; zeolites
Abstract:
... Herein, we describe a method for the quantification of Brønsted acid sites located on surfaces and in pores of hierarchical zeolite catalysts. The probe triphenylphosphine (TPP) accesses only pores bigger 0.72 nm. The signal of protonated TPP is baseline separated from other signals and can be directly quantified by ³¹P MAS NMR spectroscopy. Results are robust and are not affected by the total TPP ...
DOI:
10.1021/acs.jpcc.0c09384