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You searched for: Publication year rev 7980-2020 Remove constraint Publication year rev: 7980-2020 Subject term active sites Remove constraint Subject term: active sites Subject term carbon Remove constraint Subject term: carbon
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1. 3D Honeycomb Nanostructure Comprised of Mesoporous N-Doped Carbon Nanosheets Encapsulating Isolated Cobalt and Vanadium Nitride Nanoparticles as a Highly Efficient Electrocatalyst for the Oxygen Reduction Reaction

Author:
Zhenjiang Li; Xuehua Wang; Jing Liu; Chenghai Gao; Luhua Jiang; Yusheng Lin; Alan Meng
Source:
ACS sustainable chemistry & engineering 2020 v.8 no.8 pp. 3291-3301
ISSN:
2168-0485
Subject:
active sites; carbon; catalysts; cobalt; electrochemistry; electron transfer; encapsulation; energy conversion; methanol; nanoparticles; nanosheets; nitrides; platinum; poisoning; porous media; potassium hydroxide; protective effect; pyrolysis; silver; silver chloride; sulfuric acid; surface area; temperature; vanadium
Abstract:
... The development of high-efficiency non-noble metal catalysts for the oxygen reduction reaction (ORR) is of paramount significance to sustainable energy-conversion technologies. Herein, a three-dimensional (3D) honeycomb nanostructure comprised of mesoporous N-doped carbon nanosheets encapsulating isolated cobalt and vanadium nitride nanoparticles (denoted Co–VN–NC) is synthesized through a facile ...
DOI:
10.1021/acssuschemeng.9b06934

2. 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

3. 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

4. 3D interconnected boron- and nitrogen-codoped carbon nanosheets decorated with manganese oxides for high-performance capacitive deionization

Author:
Zhengzheng Xie; Xiaohong Shang; Jianmao Yang; Bin Hu; Pengfei Nie; Wenwen Jiang; Jianyun Liu
Source:
Carbon 2020 v.158 pp. 184-192
ISSN:
0008-6223
Subject:
X-ray photoelectron spectroscopy; active sites; adsorption; boric acid; boron; capacitance; carbon; chitosan; deionization; desalination; hydrogels; manganese; manganese dioxide; nanosheets; nitrogen
Abstract:
... The boron- and nitrogen-codoped 3D interconnected carbon nanosheets were synthesized with chitosan hydrogel and boric acid as precursors. The obtained nanosheets were interconnected to form a 3D network with thin lamellae (thickness ∼30 nm) and abundant meso-pores. The successful doping of boron and nitrogen atoms was proved by X-ray photoelectron spectroscopy (XPS). Following the decoration of ma ...
DOI:
10.1016/j.carbon.2019.12.004

5. A Ce–Fe Oxygen Carrier with a Core–Shell Structure for Chemical Looping Steam Methane Reforming

Author:
Xianglei Yin; Shen Wang; Rong Sun; Shouxi Jiang; Laihong Shen
Source:
Industrial & engineering chemistry process design and development 2020 v.59 no.21 pp. 9775-9786
ISSN:
1520-5045
Subject:
active sites; carbon; hydrogen; hydrogen production; iron oxides; methane; oxygen; process design; steam; synthesis gas
Abstract:
... Chemical looping steam methane reforming (CLSMR) is capable of both syngas and hydrogen generation, and an oxygen carrier is a key issue for CLSMR. In this work, a core–shell-structured Fe@Ce oxygen carrier is presented. With iron oxide nanocores covered by a ceria shell, this oxygen carrier integrates the advantages of both superior ion conductivity of ceria and high oxygen storage capacity of ir ...
DOI:
10.1021/acs.iecr.0c00055

6. A Proton Wire Mediates Proton Coupled Electron Transfer from Hydroxyurea and Other Hydroxamic Acids to Tyrosyl Radical in Class Ia Ribonucleotide Reductase

Author:
Adam R. Offenbacher; Bridgette A. Barry
Source:
Journal of physical chemistry 2020 v.124 no.2 pp. 345-354
ISSN:
1520-5207
Subject:
DNA replication; Escherichia coli; Fourier transform infrared spectroscopy; X-radiation; active sites; adenosine triphosphate; aspartic acid; carbon; cysteine; electron transfer; energy conversion; glutamic acid; humans; hydrogen bonding; hydroxamic acids; hydroxylamine; hydroxyurea; iron; isotope labeling; ligands; mice; protons; ribonucleotide reductase; solar energy; solvents; stable isotopes
Abstract:
... Proton-coupled electron transfer (PCET) is fundamental to many important biological reactions, including solar energy conversion and DNA synthesis. For example, class Ia ribonucleotide reductases (RNRs) contain a tyrosyl radical-diiron cofactor with one aspartate ligand, D84. The tyrosyl radical, Y122•, in the β2 subunit acts as a radical initiator and oxidizes an active site cysteine in the α2 su ...
DOI:
10.1021/acs.jpcb.9b08587

7. A char-clay composite catalyst derived from spent bleaching earth for efficient ozonation of recalcitrants in water

Author:
Lu Liu; Yi Li; Brandon A. Yoza; Kanghong Hao; Qing X. Li; Yiming Li; Qinghong Wang; Shaohui Guo; Chunmao Chen
Source:
Science of the total environment 2020 v.699 pp. 134395
ISSN:
0048-9697
Subject:
active sites; benzoic acid; bleaching; carbon; catalysts; catalytic activity; heat; hydroxyl radicals; liquids; mineralization; oxygen; ozonation; ozone; singlet oxygen; superoxide anion; wastewater
Abstract:
... Catalytic ozonation is an efficient process that can be utilized to degrade recalcitrant organics. Char-clay composite derived from refinery spent bleaching earth (SBE) is an economical and readily available catalyst that can be used during the ozonation treatment of recalcitrants in wastewater. Four catalysts of SBE-N₂-650, SBE-N₂-850, SBE-O₂-650, and SBE-O₂-850 were prepared by heating the SBE a ...
DOI:
10.1016/j.scitotenv.2019.134395

8. A controllable strategy for the self-assembly of WM nanocrystals/nitrogen-doped porous carbon superstructures (M = O, C, P, S, and Se) for sodium and potassium storage

Author:
Xiaojuan Jiao; Xiaojie Liu; Beibei Wang; Gang Wang; Xiujuan Wang; Hui Wang
Source:
Journal of materials chemistry A 2020 v.8 no.4 pp. 2047-2065
ISSN:
2050-7496
Subject:
active sites; carbon; carbonization; electrical conductivity; electrodes; energy; ethanol; heat treatment; nanocrystals; potassium; selenides; selenium; silica; sodium; sulfur
Abstract:
... Complex superstructures assembled from simple building blocks have attracted a wide range of interest in engineering materials due to their synergistic and enhanced properties. Herein, a controllable and effective strategy to assemble hierarchical superstructures using a W-polydopamine (W-PDA) complex as the binder and SiO₂@C solid spheres as the blocks is demonstrated. The micro-sized complex 3D ...
DOI:
10.1039/c9ta11312f

9. A coupling technology of capacitive deionization and MoS2/nitrogen-doped carbon spheres with abundant active sites for efficiently and selectively adsorbing low-concentration copper ions

Author:
Zhengle Hao; Yanmeng Cai; Yue Wang; Shichang Xu; Jixiao Wang
Source:
Journal of colloid and interface science 2020 v.564 pp. 428-441
ISSN:
0021-9797
Subject:
X-ray photoelectron spectroscopy; active sites; adsorption; anodes; carbon; cathodes; copper; deionization; electrodialysis; electroplating; evaporation; ferric chloride; heavy metals; ions; iron; molybdenum; molybdenum disulfide; sodium; sodium chloride; wastewater
Abstract:
... Conventional techniques like electrodialysis, evaporation concentration cannot efficiently and selectively separate valuable heavy metals ions (VHMI) from electroplating rinse wastewater due to VHMI’s low concentration and other ions’ competitive adsorption. To realize the separation, a coupling technology was proposed which combines capacitive deionization (CDI) technique suitable for separating ...
DOI:
10.1016/j.jcis.2019.12.063

10. A facile strategy based on the metal-free design of carbon to deliver an insight into the active sites for liquid phase carbocatalysis

Author:
Shuchang Wu; Xiaoli Pan; Shutao Xu; Yangming Lin; Hua Yan; Guodong Wen; Jiangyong Diao; Hongyang Liu
Source:
Chemical communications 2020 v.56 no.26 pp. 3789-3792
ISSN:
1364-548X
Subject:
active sites; carbon; catalysts; catalytic activity; chemical reduction; liquids; nitrobenzenes
Abstract:
... An effective method to study the active sites for carbocatalysis is proposed based on designing a carbon catalyst in the absence of metal as the growth catalyst. The results suggest that the oxygenated groups on the aromatic carbons are mainly responsible for the catalytic reduction of nitrobenzene and some other reactions. ...
DOI:
10.1039/c9cc09918b

11. A metal and nitrogen doped carbon composite with both oxygen reduction and evolution active sites for rechargeable zinc–air batteries

Author:
Jinjie Fang; Xuejiang Zhang; Xingdong Wang; Di Liu; Yanrong Xue; Zhiyuan Xu; Yufeng Zhang; Chun Song; Wei Zhu; Zhongbin Zhuang
Source:
Journal of materials chemistry A 2020 v.8 no.31 pp. 15752-15759
ISSN:
2050-7496
Subject:
active sites; air; batteries; carbon; carbon nanotubes; catalysts; chemical reduction; electrodes; energy density; energy efficiency; nanoparticles; nitrogen; oxygen; renewable energy sources
Abstract:
... Rechargeable zinc–air batteries (ZABs) are promising renewable energy storage devices due to their high energy density and preeminent safety. However, they still require highly active and stable oxygen reduction/evolution reaction (ORR/OER) bi-functional catalysts to promote their performance. Here, we report the synthesis of Fe,Ni on N doped carbon sheets supported on N doped carbon nanotubes (Fe ...
DOI:
10.1039/d0ta02544e

12. A metal free electrocatalyst for high-performance zinc-air battery applications with good resistance towards poisoning species

Author:
Tayyaba Najam; Syed Shoaib Ahmad Shah; Hassan Ali; Zhaoqi Song; Haohao Sun; Zhengchun Peng; Xingke Cai
Source:
Carbon 2020 v.164 pp. 12-18
ISSN:
0008-6223
Subject:
active sites; air; batteries; carbon; catalysts; catalytic activity; cobalt oxide; electric potential difference; electrochemistry; energy density; nanospheres; nitrites; nitrogen oxides; platinum; sulfites; sulfur oxides
Abstract:
... The trace amount of poisoning species in air, such as SOₓ and NOₓ, greatly degrade the performance of zinc-air battery, as they block the active sites of conventional metal containing electrocatalysts. To overcome this challenge, a catalyst with enhanced electrocatalytic properties and good resistance towards the small molecular poisons should be prepared. In this work, we synthesized a P, N dual- ...
DOI:
10.1016/j.carbon.2020.03.036

13. A newly synthesized green corrosion inhibitor imidazoline derivative for carbon steel in 7.5% NH4Cl solution

Author:
Adnan Munis; Tianyu Zhao; Maosheng Zheng; Ata Ur Rehman; Feng Wang
Source:
Sustainable chemistry and pharmacy 2020 v.16 pp. 100258
ISSN:
2352-5541
Subject:
active sites; ammonium chloride; carbon; corrosion; dielectric spectroscopy; green chemistry; microwave radiation; quantum mechanics; solvents; sorption isotherms; steel; temperature; weight loss
Abstract:
... Corrosion and corrosion inhibition behaviors of steel Q-235 were studied in 7.5% NH₄Cl solution with the newly synthesized inhibitor by potentiodynamic polarization together with tests of electrochemical impedance spectroscopy and weight loss measurements in 298–338 K temperature range. The new inhibitor 2-(2-heptadecyl-4, 5-dihydro-1H-imidazole-1-yl) ethanol (HDIE) is synthesized with the help of ...
DOI:
10.1016/j.scp.2020.100258

14. A rational synthesis of single-atom iron–nitrogen electrocatalysts for highly efficient oxygen reduction reaction

Author:
Juanjuan Huo; Li Lu; Ziyan Shen; Yan Liu; Jiaojiao Guo; Quanbing Liu; Yong Wang; Hao Liu; Minghong Wu; Guoxiu Wang
Source:
Journal of materials chemistry A 2020 v.8 no.32 pp. 16271-16282
ISSN:
2050-7496
Subject:
active sites; carbon; catalysts; catalytic activity; electrochemistry; energy; iron; oxygen; pyrolysis; simulation models
Abstract:
... Developing low-cost nonprecious catalysts to replace Pt-based material is of great significance and importance for high-performance energy devices. Designing highly efficient, stable, and economic oxygen reaction electrocatalysts with atomically-dispersed metal–N–C active sites through an effective strategy is highly desired for the oxygen reduction reaction (ORR). Currently, the preparation of mo ...
DOI:
10.1039/d0ta04798h

15. A robust and highly active hydrogen evolution catalyst based on Ru nanocrystals supported on vertically oriented Cu nanoplates

Author:
Dipak V. Shinde; Tathiana Midori Kokumai; Joka Buha; Mirko Prato; Luca De Trizio; Liberato Manna
Source:
Journal of materials chemistry A 2020 v.8 no.21 pp. 10787-10795
ISSN:
2050-7496
Subject:
active sites; carbon; catalysts; copper; copper nanoparticles; electrochemistry; electrodes; electroplating; hydrogen production; nanocrystals; platinum; porous media; ruthenium; surface area
Abstract:
... Pt nanoparticles deposited on mesoporous carbon (Pt/C) represent a benchmark catalyst for the hydrogen evolution reaction (HER) in both acid and alkaline conditions. However, it shows an order of magnitude lower activity under alkaline media compared to acid media. Moreover, the activity of this catalyst decreases rapidly under operational conditions due to both migration and aggregation of the me ...
DOI:
10.1039/d0ta03475d

16. A salt induced gelatin crosslinking strategy to prepare Fe-N doped aligned porous carbon for efficient oxygen reduction reaction catalysts and high-performance supercapacitors

Author:
Pengfei Tian; Yanhui Wang; Wei Li; Shiwei Song; Shuyu Zhou; Hongwei Gao; Hanqing Xu; Xueqing Tian; Jianbing Zang
Source:
Journal of catalysis 2020 v.382 pp. 109-120
ISSN:
0021-9517
Subject:
active sites; calcium chloride; capacitance; carbon; catalysts; catalytic activity; crosslinking; durability; electrochemical capacitors; electrochemistry; electrodes; electrolytes; gelatin; microrelief; platinum; sodium chloride
Abstract:
... The preparation of low-cost, high-efficiency and stable oxygen reduction reaction (ORR) catalysts is highly anticipated but remains a challenge. Herein, a novel strategy of CaCl₂ solution inducing gelatin crosslinking and acting as aligned pore template was put forward for preparation of Fe-N doped aligned hierarchical porous carbon. Furthermore, the microtopography and length of aligned pore can ...
DOI:
10.1016/j.jcat.2019.12.011

17. A simple and recyclable molten-salt route to prepare superthin biocarbon sheets based on the high water-absorbent agaric for efficient lithium storage

Author:
Xingtao Qi; Hai Zhang; Chao Li; Deliang Chen; Chenghua Sun; Zhenyu Yang
Source:
Carbon 2020 v.157 pp. 286-294
ISSN:
0008-6223
Subject:
active sites; adsorption; biomass; carbon; electrodes; electron transfer; energy; ions; lithium; nanosheets
Abstract:
... Due to its sustainability, biomass materials shows great potential in replacing mineral carbon source to fabricate high-energy electrode materials, and efficient routes have been explored to synthesize and regulate biomass-derived carbonaceous materials with rational structures to enable their applications. Herein, a simple and recyclable molten-salt route is used to synthesize porous ultrathin bi ...
DOI:
10.1016/j.carbon.2019.10.050

18. A single-liquid miniature biofuel cell with boosting power density via gas diffusion bioelectrodes

Author:
Jing Wan; Li Mi; Zhaoyan Tian; Quan Li; Songqin Liu
Source:
Journal of materials chemistry B 2020 v.8 no.16 pp. 3550-3556
ISSN:
2050-7518
Subject:
active sites; air; anodes; aqueous solutions; blood serum; carbon; cathodes; glucose; glucose oxidase; humans; immobilized enzymes; laccase; microbial fuel cells; microelectrodes; oxygen; paper; solubility; wettability
Abstract:
... The low solubility of gas molecules in aqueous solutions has limited the power density output of enzymatic biofuel cells. Herein, a single-liquid miniature glucose–O₂ fuel cell was constructed by using gas diffusion electrodes, which were prepared by immobilizing glucose oxidase (GOx) or laccase (Lac) modified on a porous structured carbon paper (CP). Due to the fast and direct O₂ diffusion from a ...
DOI:
10.1039/c9tb02100k

19. A strategy based on liquid-liquid-refining extraction and high-speed counter-current chromatography for the bioassay-guided separation of active compound from Taraxacum mongolicum

Author:
Yi Yang; Yunxiao Wang; Wenqiang Zeng; Jing Tian; Xuan Zhao; Jinlong Han; Dezhi Huang; Dongyu Gu
Source:
Journal of chromatography 2020 v.1614 pp. 460727
ISSN:
0021-9673
Subject:
Taraxacum mongolicum; active ingredients; active sites; alpha-amylase; carbon; catalytic activity; computer simulation; countercurrent chromatography; enzyme activity; enzyme inhibition; ethyl acetate; hydrogen bonding; hydrophobic bonding; inhibitory concentration 50; luteolin; models; nuclear magnetic resonance spectroscopy; solvents; stable isotopes; van der Waals forces
Abstract:
... The research of natural active substances is facing the problems of low separation efficiency and active component loss due to the complex composition of natural extracts. In this study, a strategy based on liquid-liquid-refining extraction and high-speed counter-current chromatography was established to solve this problem. Separation of an active compound with the α-amylase inhibitory activity fr ...
DOI:
10.1016/j.chroma.2019.460727

20. A strategy to unlock the potential of CrN as a highly active oxygen reduction reaction catalyst

Author:
Junming Luo; Xiaochang Qiao; Jutao Jin; Xinlong Tian; Hongbo Fan; Demei Yu; Wenlong Wang; Shijun Liao; Neng Yu; Yijie Deng
Source:
Journal of materials chemistry A 2020 v.8 no.17 pp. 8575-8585
ISSN:
2050-7496
Subject:
active sites; adsorption; batteries; carbon; catalysts; chromium; cobalt; electrochemistry; electrons; ethanol; fuel cells; iron; nanoparticles; nitrides; oxygen; platinum
Abstract:
... Developing cheap and highly active oxygen reduction reaction (ORR) electrocatalysts is of great importance for fuel cells and Zn–air batteries. Transition-metal nitrides are theoretically promising ORR catalysts, but their actual ORR performance is disappointing. Insufficient d electrons, low exposure of active sites and low conductivity are the three obstacles preventing transition-metal nitrides ...
DOI:
10.1039/c9ta14085a