ChemCatChem
·
2021
·Vol. 14
·期 3
·e202101716
·
IF 5.686
Yingying Zhang,Haibo Zhu,Qiangwen Fan,Liu Yang,Zongbo Xie,Zhang-Gao Le
Graphical Cobalt catalysis : An efficient cobalt-catalyzed redox-neutral sulfonylative coupling of boronic acids and ammonium salts to afford (hetero)aryl alkyl sulfones by using potassium metabisulfite has been realized. Various functional sulfones were obtained by using commercially available and air-stable CoCl 2 in combination with phenanthroline ligand. In addition, various carbon based electrophiles, including diaryliodonium salts, heteroaryl halides, and carbonates were compatible. This redox-neutral catalytic transformation proceeds well without additional base and shows broad functional-group tolerance. An efficient cobalt-catalyzed redox-neutral sulfonylative coupling to afford (hetero)aryl alkyl sulfones from boronic acids, ammonium salts and potassium metabisulfite has been realized. Commercially available and air-stable CoCl 2 , in combination with phenanthroline ligand, is sufficient to achieve rapid and high-yielding conversion of the reactants into the corresponding sulfones. This practical transformation proceeds smoothly through C−N bond cleavage under redox-neutral catalytic conditions and shows broad functional-group tolerance. Other carbon based electrophiles, including diaryliodonium salts, heteroaryl halides, and carbonates were compatible. Further transformation of aryl alkyl sulfones then allows conversion into olefins, alkenyl sulfones and halogenated sulfones, respectively, in a one-pot process.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2019
·
IF 3.674
Xiulun Sun,Xinjie Liu,Rongmei Liu,Xueying Sun,Anran Li,Wen Li
We reported a new and facile synthesis route to prepare polyaniline (PANI) nanowire@Co-Fe LDHs nanosheets in two steps. The PANI@Co-Fe LDHs has excellent OER activity with a small overpotential of 261 mV at the current density of 10 mA·cm −2 and a small Tafel slope of 67.85 mV·dec −1 . The PANI@Co-Fe LDHs also has long-term performance and stability. The excellent electrocatalytic performance of the catalyst depends on the good electrical conductivity of PANI and the effect of the two-dimensional (2D) layered structure of Co-Fe LDHs. The work opens a new application for energy storage and conversion.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
ChemElectroChem
·
2019
·Vol. 6
·期 5
·1574-1581
·
IF 3.975
Pu Wang,Shuang Hou,Fang Pang,Miao Liu,Yanxin Li,Tiezhong Liu,Yizhen Luo,YaMeng Fan,Lingzhi Zhao
Graphical In the mill : Unique hierarchical mosaic-structure SiO x /C@CoO nanosheets, with both SiO x and graphite particles embedded in a CoO layered structure, are successfully fabricated through a high-energy ball-milling process and through a one-step hydrothermal process to form a 3D hierarchical mosaic structure. The unique combination of the CoO and SiO x /C can accommodate the large volume changes and retain the structural integrity of the nanosheets, maintaining the cycling stability and rate capability of SiOx/C@CoO electrode materials. Unique hierarchical mosaic-structure SiO x /C@CoO nanosheets were successfully synthesized from SiO x /C nanospheres embedded in CoO nanosheets through a high-energy ball milling and hydrothermal self-assembly process. The SiO x /C@CoO material exhibited good cyclic performance with a reversible discharge capacity of 1079 mAh g −1 over 250 cycles at a current density of 1000 mA g −1 . It also displayed an excellent rate capability (with an average specific reversible discharge capacity of 777.8 mAh g −1 at 2000 mA g −1 and 480 mAh g −1 at 5000 mA g −1 ). The stable skeleton structure of SiO x /C-embedded CoO nanosheets and the synergistic effect between the two materials should be responsible for the improvement of the lithium storage. This work proposes a feasible approach to promote CoO application in lithium-ion batteries.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Huijing Liu,Yijun Li,Yunling Pan,Jianhui Xie,Bing Li,Zhenguo Guo,Tai-Chu Lau
The development of efficient and cost-effective electrocatalysts for hydrogen evolution reaction (HER) is of current interest. Pyrolysis of 3d metal complexes or mixtures of 3d metal ions and N-containing organic ligands has been found to be an efficient way to afford cost-effective metal- and N-doped carbon electrocatalysts for HER. However, due to the multiple-components nature of the catalysts, it is a challenge to clarify the role of each component. Herein, we report a facile approach to prepare Co- and N-doped carbon catalysts with carbon nanotubes uniformly grafted over the carbon layers via pyrolysis of a Co complex precursor bearing 2,4-diamino-6-pyridyl-1,3,5-triazine ligand. Among the prepared catalysts, Co–N/CNT/C-850 exhibits the best performance as a pH-universal electrocatalyst for HERs, which requires small overpotentials of 120, 190, and 134 mV to achieve a current density of 10 mA cm–2 in 1 M KOH, 1 M phosphate buffer solution (PBS, pH = 7), and 0.5 M H2SO4, respectively. Experimental results and theoretical calculations revealed that the Co2+ dopant played a vital role in tuning the electronic structure of the carbon skeleton, leading to boosted HER catalytic activity of adjacent carbon atoms. Our work should provide insight into the design of metal carbon composites materials for energy conversion.
研究领域:
材料科学
·
电化学
·
理论计算
✓ 已验证
DOI
高影响因子
Chemical Engineering and Processing-Process Intensification
·
2019
·
IF 3.031
Wenbin Xie,Libo Zhang,Jianyu Yang,Lihua Zhang,Shaohua Ju,Yaoyao Luo
Separation of Zn 2+ from sulphate solution containing Ni 2+ and Co 2+ using di-(2-ethylhexyl)phosphoric acid (D2EHPA) has been carried out in capillary microreactors. Well-defined slug flows are formed at total flow rates of 0.1–4 mL/min, and the slugs size and specific interfacial area are determined. The effects of saponification degree of D2EHPA, extractant concentration, and residence time on extraction and separation of these three metal ions are investigated. Meanwhile, conventional batch experiments at 94 s and equilibrium experiments at 8 h are also done in parallel at different extractant concentrations. Compared with conventional batch experiments, better extraction and separation performance, e.g. 2.7–38.9 times higher of β Zn/Ni and 3.9–34.9 times higher of β Zn/Co , is obtained in the slug flow microreactor. In addition, the overall volumetric mass transfer coefficient k L a and overall mass transfer coefficient k L are measured. Compared with other microreactors and the batch mixer-settler, the used slug flow microreactor shows higher k L a values of Zn.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
LUMINESCENCE
·
2020
·Vol. 36
·期 1
·4-10
·
IF 1.855
Liguo Ji,Chengliang Yang,Huijie Li,Nan Yang,Yutian Fu,Linlin Yang,Qingzhi Wang,Guangjie He
A novel reactive fluorescent probe for cobalt ions was prepared based on integration of thiourea functional groups, coumarin, and naphthalimide fluorophores. There was no fluorescence observed for the probe itself, however, in the presence of cobalt ions, catalytic decomposition occurred for the probe and coumarin molecular fragments were produced that emitted blue fluorescence. This enabled the probe to be used as a ‘turn on’ reagent for detection of cobalt ions. Under physiological pH conditions and in appropriate solvent systems, an obvious fluorescence enhancement for cobalt ions was observed in selective experiments. Competition experiments indicated that cobalt ions could still induce fluorescence enhancement in the presence of other metal ions. Sensitivity experiments showed that the detection limit for cobalt ions was 6.0 nM. Dynamics research demonstrated that the catalytic process was a pseudo-first-order reaction and the reaction constant (k obs ) was calculated to be 1.49 × 10 −2 min −1 . In addition, the mechanism of catalytic decomposition could be demonstrated using electrospray ionization mass spectrometry and thin layer chromatography experiments. Cell fluorescence imaging experiments demonstrated that the probe could be used to detect cobalt ions in living HeLa cells.
研究领域:
生物化学
·
分析化学
·
细胞生物学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2013
·Vol. 38
·期 25
·10191-10195
·
IF 3.548
Zhuobin Yu,Qiang Zhao,Genyan Hao,Wen Yuan,Jinping Li
A weakly acidic H 3 BO 3 solution (pH = 5.1) was used to synthesize new oxygen-evolution catalysts for water splitting under mild conditions. Two novel oxygen-evolution catalysts, Co–BA i and Mn–BA i (BA i = inorganic boric acid), were obtained in the H 3 BO 3 solution with added Co 2+ and Mn 2+ , respectively. The average oxygen evolution rate in the H 3 BO 3 solution with Co 2+ was 0.3133 μmol/h, about 70 times greater than the rate without a metal ion ; the rate with Mn 2+ was 1.13 μmol/h, about 250 times greater. The phases, morphologies, and compositions of the Co–BA i and Mn–BA i catalysts were analysed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy .
研究领域:
材料化学
·
电催化
·
能源科学
·
无机化学
·
可持续能源技术
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2017
·Vol. 4
·期 11
·1791-1797
·
IF 4.036
Jiangli Meng,Jiaqi Fu,Xiaoxuan Yang,Meijie Wei,Song Liang,Hong-Ying Zang,Huaqiao Tan,Yonghui Wang,Yangguang Li
The development of stable, highly active and cheap electrocatalysts towards the oxygen evolution reaction (OER) has been an ongoing challenge due to practical problems such as slow kinetics and high overpotential. Herein, we utilized a one-pot hydrothermal method to prepare cobalt/nickel molybdate hierarchical microflowers on conductive carbon cloth (MMoO4-CC, M = Co, Ni) as three-dimensional self-supported electrodes for the oxygen evolution reaction. CoMoO4-CC showed better catalytic activity than NiMoO4-CC. Benefiting from the synergistic effect of a large active area, fast charge and mass transport as well as a three-dimensional conducting path, the CoMoO4-CC nanosheet electrode showed a large current density and a relatively low starting potential, delivering 10 mA cm−2 current densities at an overpotential of 290 mV and a Tafel slope of 94 mV dec−1. Furthermore, the CoMoO4-CC nanomaterial shows better electrocatalytic stability than IrO2-CCa, which could be a promising electrocatalyst for large-scale water oxidation.
研究领域:
电催化
·
材料科学
·
能源化学
·
电化学
·
纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2014
·Vol. 19
·期 2
·497-506
·
IF 2.234
Jiang Liqing,Cui Lili,He Xingquan
Cobalt 5,10,15,20-tetrakis(4-pyridyl)porphyrin (CoTPyP) micro/nanoparticles assembled on poly(sodium-p-styrenesulfonate) (PSS) modified reduced graphene oxide (PSS-rGO) as a nonnoble catalyst for oxygen reduction reaction (ORR) was prepared by an in situ solvothermal synthesis method. The CoTPyP/PSS-rGO micro/nanocomposite was characterized by UV-vis spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM) techniques. Cyclic voltammetry (CV) measurement result disclosed that CoTPyP/PSS-rGO possesses quite high electrochemically accessible surface area, which was more than tripled as large as the bare glassy carbon (GC) electrode. Rotating disk electrode (RDE) and rotating ring-disk electrode (RRDE) techniques were employed to study the catalytic activity and the ORR mechanism of as-synthesized CoTPyP/PSS-rGO catalyst in an alkaline medium. Linear sweep voltammetry (LSV) tests showed that the half-wave potential for ORR on the CoTPyP/PSS-rGO catalyst was found to be around −0.22 V vs. saturated calomel electrode (SCE), which was similar to that on Pt/C (−0.20 V vs. SCE). RRDE results displayed that the percentage of hydrogen peroxide yielded on the CoTPyP/PSS-rGO composite was less than 20 %, and the ORR process mainly proceeded via an almost direct 4-electron pathway. Moreover, the assembled CoTPyP/PSS-rGO catalyst possessed good stability and excellent tolerance to the crossover effect of methanol for ORR.
研究领域:
电化学
·
纳米材料
·
能源材料
·
催化化学
·
表面科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2015
·
IF 6.723
Liang-Liang Feng,Guo-Dong Li,Yipu Liu,Yuanyuan Wu,Hui Chen,Yun Wang,Yong-Cun Zou,Dejun Wang,Xiaoxin Zou
Splitting water to produce hydrogen requires the development of non-noble-metal catalysts that are able to make this reaction feasible and energy efficient. Herein, we show that cobalt pentlandite (Co9S8) nanoparticles can serve as an electrochemically active, noble-metal-free material toward hydrogen evolution reaction, and they work stably in neutral solution (pH 7) but not in acidic (pH 0) and basic (pH 14) media. We, therefore, further present a carbon-armoring strategy to increase the durability and activity of Co9S8 over a wider pH range. In particular, carbon-armored Co9S8 nanoparticles (Co9S8@C) are prepared by direct thermal treatment of a mixture of cobalt nitrate and trithiocyanuric acid at 700 °C in N2 atmosphere. Trithiocyanuric acid functions as both sulfur and carbon sources in the reaction system. The resulting Co9S8@C material operates well with high activity over a broad pH range, from pH 0 to 14, and gives nearly 100% Faradaic yield during hydrogen evolution reaction under acidic (pH 0), neutral (pH 7), and basic (pH 14) media. To the best of our knowledge, this is the first time that a transition-metal chalcogenide material is shown to have all-pH efficient and durable electrocatalytic activity. Identifying Co9S8 as the catalytically active phase and developing carbon-armoring as the improvement strategy are anticipated to give a fresh impetus to rational design of high-performance noble-metal-free water splitting catalysts.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Depeng Song,Zewen Yang,Qing Zhao,Xiaolin Sun,Yue Wu,Yuan Zhang,Jing Gao,Cheng Wang,Li Yang,Takeo Ohsaka,Futoshi Matsumoto,Jianfei Wu
Li-rich cathodes have potential for use in next-generation Li-ion batteries (LIBs) owing to their high specific capacity and low cost. However, their intrinsic cycling decay and voltage fading limit practical applications. In addition, these cathodes contain Co, which is nonrenewable, scarce, and expensive. This situation severely limits the rapid and sustainable development of low-cost LIBs. This paper introduces a novel dilute electrolyte to overcome these limitations based on the Co-free Li-rich Li1.2Mn0.54Ni0.26O2 (LMNO) cathode. An even and robust cathode-electrolyte interface (CEI) formed on the surface of LMNO further protects it from side reactions in the dilute electrolyte. This Co-free Li-rich cathode exhibits the best electrochemical performance reported to date among Li-rich cathodes in terms of outstanding cycling stability (capacity retention of 99.8% at 0.5 C) and dramatically suppressed voltage fading (only 0.3% after 100 cycles). This study demonstrates the potential of Co-free Li-rich cathodes for applications in next-generation LIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ChemElectroChem
·
2021
·Vol. 8
·期 8
·1531-1536
·
IF 4.59
Zhaowei Ren,Zhenxin Zhao,Kun Zhang,Xiaomin Wang,Yongzhen Wang
Graphical Read my LiPSs : A CoSe 2 /CC composite interlayer structure limiting liquid lithium polysulfides (LiPSs) is prepared to address the problem of polysulfides susceptibility to dissolution in lithium−sulfur batteries, which accelerates the reduction of soluble LiPSs and the reuse of insoluble product Li 2 S. The electrochemical results confirm that CoSe 2 /CC achieves high capacity and good cycling stability as an interlayer, and maintains high Coulombic efficiency under high loading and low current conditions, indicating that the shuttle of LiPSs is effectively suppressed. Lithium−sulfur batteries have been regarded as the next generation of competitive batteries because of their high theoretical capacity and energy density. However, the commercial development of lithium−sulfur batteries is restricted by the shuttle action of polysulfides and volumetric expansion of sulfur. Herein, we developed cobalt selenide/carbon cloth composites (CoSe 2 /CC) as the interlayer. CoSe 2 can not only limit the shuttling of polysulfides by Co−S bonds and accelerate the catalytic conversion kinetics of sulfur chemistry, but also increases the electrical conductivity of materials, leading to an excellent cycle stability. As a result, the cell with CoSe 2 /CC interlayer has a high initial capacity of 1420 mAh g −1 at 0.1 C and keeps high-capacity retention of 596 mAh g −1 after 500 cycles at 1 C rate (70 %). Subsequent electrochemical tests show that CoSe 2 /CC enhance the electrochemical behavior of the polysulfides. Therefore, the hierarchical CoSe 2 /CC composites have promising application potential in lithium−sulfur batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）