ELECTROCHIMICA ACTA
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2022
·
IF 7.336
Song-Yi Liao,Shuai-Fu Cui,Yue-Zhu Li,Wei-Xiang Cheng,Xing-Wen Huang,Jing Zhang,Ting-Ting Cui,Xu-Gang Shu,Yong-Gang Min
In this work, the wrinkled, flexible, and layered nitrogen-doped Ti 3 C 2 T x (shorten as N-MXene) is synthesized by using cyanamide as N-dopants. The changeable (002) plane spacing and the attached functional groups of N-MXene are detected by XRD and XPS analyses in details, respectively. The microscopic morphology of N-MXene is characterized by SEM and TEM, which demonstrates its wrinkled and flexible characteristics. When the wrinkled N-MXene being added into the LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) as conductive additive, the attained electrodes obtain enhanced electrochemical performances at the appropriate weight ratio (namely 2.5-N-MXene with 2.5 wt.%). The 2.5-N-MXene delivers “extra” capacity of 226.9 mAh/g at 0.1 C (20 mA/g) current density. The “extra” capacity is assigned to Li ions intercalation/extraction from the wrinkled/flexible/layered N-MXene. Moreover, based on the analyses of CV and dQ/dV curves, the wrinkled/flexible N-MXene additive could effectively inhibit the phase transition of M↔H2 of NCM811 and alleviate the volume change of the particles in the circulation. From DFT simulation, the N-MXene is more capable of preventing Ni/Co/Mn from dissolving and migrating to the negative electrode to form dendrites through adsorption. Therefore, the N-MXene should be a very competitive conductive agent to improve the mechanical and electrochemical properties of high nickel cathode materials.
研究领域:
材料科学
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电化学
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DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
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2015
·Vol. 15
·期 6
·4608-4618
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IF 1.556
Cui Qinmin,Zhu Shudi,Yan Yingjie,Ye Quanlin,Ziener Ulrich,Cao Zhihai
In the present study, superparamagnetic Fe3O4/poly(N-isopropyl acrylamide) nanocomposites were synthesized by one-step inverse miniemulsion copolymerization of N-isopropyl acrylamide and N,N'-methylene diacrylamide. The loading of Fe3O4 nanoparticles
in the nanocomposites was 27 wt%, and the saturation moment of the nanocomposites was 12.4 emu · g−1. Fe3O4 nanoparticles were prepared through a coprecipitation method. The amount of stabilizer (poly(acrylic acid)) significantly influenced the
size and size distribution of the Fe3O4 nanoparticles, and, therefore, their magnetic properties. Superparamagnetism of the Fe3O4 nanoparticles was preserved in the nanocomposites. The effects of synthetic parameters on the particle properties, namely
surfactant loading, concentration of ferrofluid, type of lipophobe and initiator, and amount of cross-linker were investigated. Nanocomposites of Fe3O4/poly(N-isopropyl acrylamide) displayed a guava-like morphology, which they could retain after being redispersed
in polar solvents.
研究领域:
材料科学
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纳米技术
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化学工程
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DOI
高影响因子
ChemSusChem
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2020
·Vol. 13
·期 16
·4151-4158
·
IF 7.962
Huai Liu,Ning Ding,Junnan Wei,Xing Tang,Xianhai Zeng,Yong Sun,Tingzhou Lei,Huayu Fang,Tianyuan Li,Lu Lin
Graphical No base needed : N-doped carbon-supported CoCu bimetallic catalyst with enhanced O 2 activation ability and basicity is demonstrated as an effective catalyst for the oxidative esterification of 5-hydroxymethylfurfural. The introduction of Cu significantly enhances the catalytic activity, resulting in a high furan-2,5-dimethylcarboxylate yield and an impressive formation rate, paving the way for the efficient and green synthesis of sustainable bio-based polymer monomers. The direct fabrication of furan-2,5-dimethylcarboxylate (FDMC), a promising renewable monomer, from biomass-derived 5-hydroxymethylfurfural (HMF) is a cutting-edge process. In this contribution, an elaborately designed N-doped carbon-supported CoCu bimetallic catalyst (Co x Cu y -NC; x / y= 9:1, 7:3, 4:6, which represents the designed molar ratio of Co and Cu in the catalyst), which could offer a desirable FDMC yield of 95 % under mild and base-free conditions (Co 7 Cu 3 -NC, 2 bar O 2 , 80 °C, 4 h) is described for the oxidative esterification of HMF. Notably, an FDMC formation rate of 6.1 mol FDMC mol Co −1 h −1 was achieved over Co 7 Cu 3 -NC, which represents the highest catalytic efficiency so far among Co-based catalytic systems. It has been demonstrated that Cu-doping in Co 7 Cu 3 -NC catalyst brings about more active sites (Co-N x species) with stronger molecular oxygen activation ability. The increase of surface N content of Co 7 Cu 3 -NC also improves basicity of the catalyst, which favors the hydrogen abstraction process during the HMF oxidative esterification reaction. These findings may pave an efficient and green way for the synthesis of sustainable bio-based polymer monomers.
研究领域:
催化化学
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生物质转化
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绿色化学
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DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
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2015
·Vol. 19
·期 12
·3613-3620
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IF 2.446
Yang Suling,Li Gang,Wang Guifang,Deng Dehua,Qu Lingbo
A novel electrochemical sensor based on Fe 2 O 3 nanoparticles supported on N-doped graphene (Fe 2 O 3 NPs/N–GR) has been fabricated for electrocatalytic oxidation and detection of L-cysteine. The Fe 2 O 3 NPs/N–GR was characterized by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy (XPS), and electrochemical methods. The electrochemical behavior of L-cysteine at Fe 2 O 3 NPs/N–GR was investigated by voltammetry. The Fe 2 O 3 NPs/N–GR showed a very efficient electrocatalytic activity for the oxidation of L-cysteine in 0.1 M phosphate buffer solution (PBS, pH 7.0). The oxidation peak currents increased dramatically at Fe 2 O 3 NPs/N–GR-modified electrode. The potential utility of the sensor was demonstrated by applying it to the analytical determination of L-cysteine. Experimental results showed that the electrocatalytic current increased linearly with L-cysteine concentration in the range of 0.2–400 μM with a lowest detectable concentration of 0.1 μM.
研究领域:
分析化学
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生物医学工程
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材料科学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2019
·
IF 3.375
Tianwen Ma,Xiaojie Tan,Qingshan Zhao,Zhuangzhuang Wu,Fengliang Cao,Jingyan Liu,Xiaocui Wu,Hui Liu,Xiaobo Wang,Hui Ning,Mingbo Wu
In this study, we demonstrate noble metal-free Fe–N-codoped graphene nanoshells (Fe–N/GNS) derived from petroleum pitch as highly efficient and cost-effective catalysts for nitroaromatics reduction. By employing α-Fe2O3 nanoparticles simultaneously as both the hard template and the metal source, Fe–N/GNS can be facilely synthesized through the template-oriented method, followed by thermal annealing with urea for nitrogen doping. Owing to the high-dispersed synergetic Fe–N active sites as well as the hierarchical porous nanoshell structure, the Fe–N/GNS catalysts show remarkable catalytic performance and good tolerance for the reduction of nitroaromatics with NaBH4 aqueous solution. The optimized Fe–N/GNS-800 corresponds to pseudo-first-order kinetics for p-nitrophenol reduction at room temperature, with the rate constant (k) reaching 1.23 min–1. The reinforced structure also allows the catalyst to be readily recycled a dozen times without activity deterioration. This work may provide a new avenue to facilely fabricate cost-effective but powerful catalysts for nitroaromatics reduction and beyond.
研究领域:
材料科学
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催化化学
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环境化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2022
·
IF 7.139
Weilin Zhong,Chao Wang,Bo Jiang,Suqing Peng,Hailun Zhao,Riyang Shu,Zhipeng Tian,Yanping Du,Ying Chen
Combining solar energy utilization and hydrogen production is an ideal model for renewable energy development. Especially the conversion of broad-spectrum solar energy into chemical energy of hydrogen and thermal energy can enrich solar energy storage methods. Herein, novel multifunctional Au/TiO 2 @n-octadecane microcapsules with core-shell structure were design and synthesized by wet chemical reduction and electrostatic adsorption self-assembly methods for photothermal hydrogen production and thermal storage . The results showed that microencapsulation of photothermal catalysts could provide an effective reaction area and excellent dispersion stability , where hydrogen production and light to hydrogen efficiency were increased in the 43% and 0.3% respectively, compared to the nanoparticle suspension system. Based on the recorded temperature variations caused by the photothermal effect, the calculated photothermal conversion efficiency and specific absorption rate of Au/TiO 2 @n-octadecane was 25.01% and 277% higher than that of Au/TiO 2 suspension. The proposed hydrogen production and thermal storage method via multifunctional microcapsules might shed some light on the study of improving full-spectrum energy conversion efficiency of solar energy.
研究领域:
材料科学
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能源科学
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纳米技术
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2021
·
IF 6.165
Yannan Du,Hongjun Zang,Yimo Feng,Kai Wang,Yaxin Lv,Zhipeng Liu
This paper briefs the emerging strategies for the designing of catalytic systems, which direct conversion of chitin biomass monomer N -acetyl- d -glucosamine (NAG) to 3-acetylamino-5-acetylfuran was studied systemically. Twelve catalysts were investigated, and pyrazine hydrochloride ([Pyz]Cl) ionic liquid exhibited the good performance-achieving 3A5AF with yields of 36.94% from NAG . Further adding boric acid and CaCl 2 , treating at 190 °C for 60 min, the conversion rate of NAG is 100%, and the yield of 3A5AF can be increased to 69.54% in DMA. Furthermore, functional group changes before and after the reaction have been characterized by FTIR, HPLC-MS and 13 C NMR were applied to monitor the reaction process with [Pyz]Cl as the catalyst. The reactive intermediate was clearly detected by these techniques. Accordingly, a possible reaction pathway was proposed. The results of this experiment provide a mild and efficient reaction route for the degradation of biomass, and enrich the theoretical research of quaternary amine catalysts in the conversion of biomass waste into high value-added chemicals.
研究领域:
生物化学
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催化化学
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DOI
高影响因子
ANALYTICAL CHEMISTRY
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2024
·
IF 6.7
Yani Liu,Xueao Wang,Zheng Li,Liping Chen,Xinyi Cai,Zhigang Sun,Wei Cheng,Xiangjie Luo,Hai-Liang Zhu,Yong Qian
Hydrogen sulfide (H2S), a critical gas signaling molecule, and N-acetyltransferase 2 (NAT2), a key enzyme in drug metabolism, are both known active biomarkers for liver function. However, the interactions and effects of H2S and NAT2 in living cells or lesion sites remain unknown due to the lack of imaging tools to achieve simultaneous detection of these two substances, making it challenging to implement real-time imaging and precise tracking. Herein, we report an activity-based two-photon fluorescent probe, TPSP-1, for the cascade detection of H2S and NAT2 in living liver cells. Continuous conversion from TPSP-1 to TPSP-3 was achieved in liver cells and tissues. Significantly, leveraging the outstanding optical properties of this two-photon fluorescent probe, TPSP-1, has been effectively used to identify pathological tissue samples directly from clinical liver cancer patients. This work provides us with this novel sensing and two-photon imaging probe, which can be used as a powerful tool to study the physiological functions of H2S and NAT2 and will help facilitate rapid and accurate diagnosis and therapeutic evaluation of hepatocellular carcinoma.
研究领域:
生物化学
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医学影像学
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肿瘤学
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DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 21
·6384-6397
·
IF 6.177
Zhi Zhu,Reeti Kumar,Liwen Luo,Sunita Varjani,Pengwei Huo,Jonathan Woon-Chung Wong,Jun Zhao
Photocatalytic degradation of pharmaceuticals in the aquatic environment is considered a promising strategy to address water pollution. In this study, a novel photocatalyst was constructed by decorating g-C3N4 (CN) with α-MoC1−x quantum dots (α-MoC1−x-QDs) through a facile calcination method. The catalyst showed enhanced tetracycline (TC) degradation performance under visible light. The unique Mo–N surface bonding states and quantum effect leading to superior TC degradation activity (89.1%) compared to pure CN (21.8%) were reported and revealed. More importantly, the mechanism for the significant enhancement of photocatalytic activity of the catalyst was investigated by DFT (density functional theory) calculations and photo-electrochemistry measurements. The results confirmed that the effect of α-MoC1−x-QDs on CN improved the light absorption capacity obviously, and the Mo–N surface bonding states accelerated the charge migration from CN to α-MoC1−x-QDs. Moreover, the TC degradation pathway, intermediates and photogenerated carrier transfer behaviors were also discussed in depth. This research provides a new strategy for the construction of noble-metal-free co-catalyst/semiconductor composite materials in the photocatalytic degradation of antibiotics.
研究领域:
环境科学
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材料科学
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化学
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DOI
高影响因子
ChemPlusChem
·
2024
·
IF 3
Yong Wang,Xueying Lin,Xianyu Ying,Shan Hu,Hongjun Zhu
A facile C–H amination of quinazoline employing N-fluorobenzenesulfonimide (NFSI) as the amination source has been disclosed in the absence of any metal, oxidant or additive. The methodology shows a board range of quinazolines with different functional groups in moderate to good yields up to 87%. Furthermore, gram-scale reaction, desulfonylation to amine and synthesis of pharmaceutical intermediate were also investigated, which demonstrates potential applications in medicinal chemistry. A plausible amination mechanism is proposed via F+ transfer accompanied by the removal of one molecule of PhSO2F. DFT studies with experimental work suggest that the mechanism via F+ transfer is more favorable than the free radical one.
研究领域:
有机化学
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药物化学
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合成化学
✓ 已验证
DOI
PubMed
高影响因子
MOLECULES
·
2017
·Vol. 22
·期 6
·970
·
IF 2.861
Ming-Xia Song,Song-Hui Li,Jiao-Yang Peng,Ting-Ting Guo,Wen-Hui Xu,Shao-Feng Xiong,Xian-Qing Deng
Due to the rapidly growing bacterial resistance to antibiotics and the scarcity of novel agents under development, bacterial infections are still a pressing global problem, making new types of antibacterial agents, which are effective both alone and in combination with traditional antibiotics, urgently needed. In this paper, seven series ofN-arylsulfonylindole analogs5–11bearing rhodanine moieties were synthesized, characterized, and evaluated for antibacterial activity. According to the in vitro antimicrobial results, half of the synthesized compounds showed potent inhibition against four Gram-positive bacteria, with MIC values in the range of 0.5–8 µg/mL. For multidrug-resistant strains, compounds6aand6cwere the most potent, with MIC values of 0.5 µg/mL, having comparable activity to gatifloxacin, moxiflocaxin and norfloxacin and being 128-fold more potent than oxacillin (MIC = 64 µg/mL) and 64-fold more active than penicillin (MIC = 32 µg/mL) againstStaphylococcus aureusATCC 43300.
研究领域:
药物化学
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微生物学
·
感染与免疫
✓ 已验证
DOI
高影响因子
Catalysts
·
2023
·Vol. 14
·期 1
·23
·
IF 3.9
Zi-Han Zhang,An-Qi Wang,Bao-Di Ma,Yi Xu
The effective synthesis ofN-benzyl cyclo-tertiary amines using imine reductase, key components in natural products and pharmaceutical synthesis, is a green approach. Traditional methods faced challenges with enzyme activity and selectivity. This study focused on enhancingMesorhizobiumimine reductase (MesIRED) for betterN-benzyl cyclo-tertiary amine production. Through alanine scanning and consensus mutation, 12 single-siteMesIRED mutants were identified from 23 candidates, showing improved conversion ofN-benzylpyrrolidine andN-benzylpiperidine. Notably, mutants from I177, V212, I213, and A241 significantly boosted conversions. The best-performing mutant forN-benzylpyrrolidine,MesIREDV212A/I213V(M1), increased conversion from 23.7% to 74.3%. ForN-benzylpiperidine,MesIREDV212A/I177A/A241I(M2) enhanced conversion from 22.8% to 66.8%. Tunnel analysis revealed M1 and M2 have more efficient tunnels for larger product movement compared to wild-typeMesIRED. Using recombinantE. colicoexpressingMesIRED and glucose dehydrogenase (GDH), high conversions were achieved: 75.1% forN-benzylpyrrolidine (M1) and 88.8% forN-benzylpiperidine (M2). A preparative experiment resulted in 86.2% conversion and 60.2% yield forN-benzylpiperidine. This research offers an efficient method for engineering IRED, significantly improving conversion and selectivity forN-benzyl cyclo-tertiary amines, aiding drug synthesis and providing insights into rational design of other enzymes.Keywords:imine reductase;N-benzyl cyclo-tertiary amines;alanine scanning;consensus mutation;whole-cell biocatalysis;coexpression
研究领域:
生物化学
·
酶工程
·
药物合成
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）