JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2017
·
IF 4.233
Chenhu Zhang,Sun Wei,Yuehua Hu,Honghu Tang,Jiande Gao,Zhigang Yin,Qingjun Guan
Selective adsorption of tannic acid (TA) on calcite surfaces and the implications of this process for the separation of fluorite ore were studied by microflotation tests, surface adsorption experiments, zeta potential measurements, UV–vis analysis, and X-ray photoelectron spectroscopy (XPS) analysis. The microflotation tests indicated that TA, when added before sodium oleate (NaOl), could selectively depress calcite from fluorite at pH 7. Surface adsorption experiments revealed that TA hinders the interaction of NaOl with calcite. The zeta potential of calcite became more negative with TA than with NaOl. However, the characteristic features of TA adsorption were not observed on fluorite, suggesting that the dominant adsorption sites are dissimilar on the fluorite and calcite surfaces in the pulp. UV–vis spectroscopy, XPS, and solution chemistry analysis were utilized to obtain a better understanding of the mechanism for selective adsorption of TA as well as the key factors determined by the Ca 2+ and Ca(OH) + components on the mineral surfaces. A possible adsorption mechanism along with an adsorption mode is proposed for the surface interaction between TA and calcite.
研究领域:
矿物加工工程
·
表面化学
·
胶体与界面科学
·
资源利用
·
浮选化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Cheng Liu,Xinyue Zhang,Yunfei Zheng,Zijie Ren,Weng Fu,Siyuan Yang
Fluorite is easily affected by the slime coating of fine barite during the froth flotation separation. In this work, the water glass (WG) was utilized as a dispersant to improve the flotation separation performance between fluorite and barite slimes. The single minerals flotation results revealed that barite slimes could be selectively depressed by gelatinized starch (GS), while WG had little effect on the floatability of barite and fluorite using sodium oleate (NaOl) as a collector. The flotation results of artificially mixed minerals showed that the separation efficiency of fluorite from barite was significantly reduced when barite existed as slimes. However, the presence of WG could eliminate the negative effect of barite slimes on the flotation fluorite by using the reagents scheme of GS/NaOl. Zeta potential results indicated that the fluorite surface charge turned from positive to negative with the addition of WG, then the barite slimes coating was detached from the fluorite surface because of the electrostatic repulsion, allowing the cleaning fluorite surface to once again interact with NaOl. The DLVO calculation was also conducted to reveal the agglomerate and disperse of different particles in the flotation system of fluorite-barite slimes.
研究领域:
矿物加工工程
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浮选化学
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胶体与界面科学
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资源综合利用
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无机非金属材料
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Hongchao Li,Jianpeng Zou,Senlin Xie,Xian Leng,Di Gao,Xu Mao
WSe 2 films were prepared on inexpensive graphite substrate through direct-current magnetron sputtering and rapid selenization for catalytic application in the hydrogen evolution reaction (HER). The effects of the temperature and time in selenization process on the HER activity were studied in details. Scanning electron microscopy and Raman spectroscopy indicates that the graphite surface is covered by WSe 2 nanosheets . The HER activity of WSe 2 samples prepared at different conditions has been evaluated via linear sweep voltammetry. Through adjusting selenization parameters, the WSe 2 nanofilms consists of the proper nanosheets has been prepared with the optimal HER activity. It’s important to control the number, the size and crystallinity of WSe 2 nanosheets which take responsibility for the HER activity. WSe 2 electrodes prepared at 500 °C for 10 min exhibit high stability in acidic solution and get the optimal activity with an over potential around −179 mV vs reversible hydrogen electrode (RHE) at the current density of 10 mA cm −2 .
研究领域:
材料科学
·
电化学
·
纳米材料
·
催化化学
·
能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2013
·
IF 2.672
Yinfeng Li,Lina Zou,Ge Song,Kunjing Li,Baoxian Ye
The electro-polymerization of l -Theanine was investigated for the first time on glassy carbon electrode and the polymeric conditions and mechanism were discussed in detail. Hereafter, a simple and sensitive electrochemical sensor based on the poly( l -Theanine) film was established for sophoridine sensing. The electrode process of sophoridine was then studied by cyclic voltammetry and its determination was achieved by amperometry . The results revealed that the poly( l -Theanine) membrane effectively decreased the oxidation potential of sophoridine and greatly increased its response current. And this sensor, fabricated easily and simply as well as very easy surface update, showed good response for sophoridine with a wide linear range from 1.0 × 10 −6 to 1.4 × 10 −4 mol L −1 and a low detection limit of 5 × 10 −7 mol L −1 . The application of proposed method in analysis of real sample was also evaluated with good performance. This work promoted the potential applications of amino acid materials in electrochemical sensors.
研究领域:
分析化学
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电化学
·
药物分析
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生物传感
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分子诊断
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药物代谢
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·Vol. 42
·期 7
·3947-3954
·
IF 3.205
Jialei Jin,Yuanzhi Zhu,Yizhe Liu,Yang Li,Wenchao Peng,Guoliang Zhang,Fengbao Zhang,Xiaobin Fan
Producing hydrogen through hydrogen evolution reaction by electrolyzing water is a great alternative to solve the energy crisis and air pollution. Earth abundant transition-metal phosphides, especially CoP , have emerged as promising hydrogen evolution reaction catalysts for recent years. Nowadays, attention is focused on combining CoP with other materials to improve its catalytic activity . Herein, in order to get better hydrogen evolution reaction catalyst, we combined CoP nanoparticles with WS 2 nanosheets. Different CoP to WS 2 mass ratios were set to find the best catalytic activity. CoP/WS 2 composites were prepared through a simple ultrasound induced mixing method. And all the CoP/WS 2 composites have enhanced hydrogen evolution reaction catalytic activity than pure CoP nanoparticles and WS 2 nanosheets. Especially, the optimized CoP/WS 2 composite has the lowest onset overpotential of 50 mV, the largest current density of 78 mA/cm 2 at the overpotential of 300 mV, and the smallest Tafel slope of 64.63 mV/decade, indicating excellent hydrogen evolution reaction catalytic activity.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
无机功能材料
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2021
·
IF 6.498
Xiulei Fan,Zixuan Ma,Yefeng Zou,Jiaqiang Liu,Jun Hou
In recent years, tire wear particles (TWP), as the significant proportion of microplastics (MPs), has adsorbed much attention due to its widespread presence in aquatic ecosystem . Compared with typical MPs, TWP exists significant differences in composition, additives, characteristics and so on. With TWP and polypropylene (PP) as target MPs, Cd 2+ and Pb 2+ as target pollutants, the adsorption-desorption characteristics of heavy metal ions on original and aged MPs were studied. Compare with the PP, the S BET of TWP increased more significantly after the UV ageing process. Meanwhile, the zeta potential of TWP increased from −8.01 to −14.6 mV and PP from −5.36 to −9.52 mV, and the surface of the TWP were more negatively-charged. In addition, the hydrophilicity of MPs enhanced due to the increased oxygen-containing functional groups after ageing process. Compared with PP, the physicochemical properties of TWP changed more obviously during UV ageing processes. The adsorption results showed that the pseudo-second-order model could better describe the adsorption processes of Cd 2+ and Pb 2+ on MPs. Meanwhile, the orders of adsorption capacity of MPs for Cd 2+ and Pb 2+ were aged TWP > aged PP > original TWP > original PP. The phenomenon of adsorption confirmed that TWP had better vector effects for heavy metal ions than PP, and the ageing processes could enhance the adsorption capacity of MPs. Moreover, the desorption results demonstrated that, compared with PP, the TWP (with higher adsorption capacity) also had the better desorption capacity for heavy metal ions in simulated gastric fluid. Compared with PP, the TWP might cause a more serious hazard to aquatic environment and organisms. These investigations would contribute to assessing the potential environmental and biological risk of TWP, especially considering the effect of the ageing process.
研究领域:
环境科学
·
生态毒理学
·
微塑料污染
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水生生态系统
·
环境化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Mingyuan Chen,Yaxin Lv,Peilin Wu,Liuyan Dong,Xingquan He,Lili Cui
To obtain highly active electrocatalyst for the whole electrochemical water splitting is of importance to generate hydrogen. Co(OH) 2 is used as electrocatalyst towards OER, however, the performance can be improved further. Usually, to construct the interface and adjust the electronic environment of electrocatalysts are regarded as powerful ways to improve the activity. Herein, CeO 2 -Co(OH) 2 sheets supported on copper foam (CF) are fabricated by electrodeposition method. The morphology and the electron structure of metals are adjusted by changing the molar ratio of Co to Ce, thus, resulting in different electrocatalytic activity. The optimal hybrids of CeO 2 -Co(OH) 2 exhibits lower overpotentials of 188, 269 mV to reach 10 mA cm −2 towards HER and OER, respectively, and good stability. Notably, it is found that the electroactivity is extremely superior to that of bare CF as well as the counterparts in the literature. Also, we try to employ M(OH) 2 (M = Fe, Ni) to substitute Co(OH) 2 to investigate the effect of species of hydroxides on the electron interaction between CeO 2 and hydroxides, the XPS results indicate that Ce and Co shows stronger electron interaction compared to other two control hydroxides. As electrocatalysts for alkaline full water splitting, CeO 2 -Co(OH) 2 requires a cell voltage of 1.62 V to drive 10 mA cm −2 . Experimental results prove the advantages of the electron engineering and morphology control.
研究领域:
材料科学
·
电化学
·
能源化学
·
纳米材料
·
催化化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2011
·Vol. 36
·期 13
·7374-7380
·
IF 4.057
Wei Wang,Qiang Zhao,Jinxiang Dong,Jinping Li
A novel silver oxides oxygen evolving catalyst (Ag-OEC) for hydrogen production by water splitting was formed in situ on an indium tin oxide anode, in a near-neutral potassium tetraborate (K 2 B 4 O 7 ) electrolyte. The catalyst exhibited high activity and low overpotential for O 2 evolution under mild conditions. The main functional composition of the catalyst was a redox couple of Ag 2 O/AgO. Catalytic activity during oxygen evolution was evaluated by cyclic voltammetry and Tafel plot. The effects of the concentration, temperature, and pH of K 2 B 4 O 7 solution on the catalyst, and the Faradaic efficiency of the oxygen evolving reaction were examined. The results show that the Ag-OEC exhibits excellent oxygen evolution properties, with an oxygen evolving overpotential of 318 mV at a current density of 1 mA/cm 2 .
研究领域:
电催化
·
能源化学
·
材料科学
·
物理化学
·
可持续能源
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Jingxi Tie,Zhihong Zheng,Xiaomei Zheng,Yaru Hao
The water-soluble protein was extracted from Moringa oleifera seed press cake and tested its performance as a natural coagulant for removing humic acid (HA) from water solution when comparing to polyaluminum chloride (PAC), a commercial coagulant. Influencing factors including pH, coagulant dosage, temperature and suspended solid were investigated in this study. The results indicated that the coagulating efficiencies of HA using the Moringa oleifera seed protein (MOSP) were better than those by PAC under all the experimental conditions at the same dosage. MOSP could increase the zeta potential more efficiently than PAC. The Fourier transform infrared spectra revealed that no new compounds were generated during the coagulation process. Hence, adsorption and charge neutralization could be the main mechanism contributing to the HA removal using MOSP as coagulant. MOSP is an ideal natural coagulant for HA removal.
研究领域:
环境科学
·
水处理技术
·
天然产物应用
·
环境工程
·
胶体化学
✓ 已验证
DOI
高影响因子
TETRAHEDRON
·
2014
·Vol. 70
·期 47
·9033-9040
·
IF 2.817
Tao Liu,Meng-Meng Liu,Xiao-Wen Zheng,Chong-Yang Du,Xiang-Yang Cui,Lu Wang,Ling-Li Han,Zhang-Yu Yu
The redox reactions of p -hydroquinone and pyrocatechol undergo a two-proton-two-electron process in aqueous solution. We calculated their redox potentials at the B3LYP/6-311+G(d,p) level, and verified the values by employing cyclic voltammetry experiments. Then we selected seven substituent groups (–F, –Cl, –OH, –COOH, –CN, –NH 2 , and –NO 2 groups) to systematically investigate the substituent effect , including the sort, position, and number of the substituent, on the redox potentials of p -hydroquinone and pyrocatechol. The calculated results show that –NH 2 and –OH groups can decrease the redox potentials, while –F, –Cl, –COOH, –CN, and –NO 2 groups increase the potential values of p -hydroquinone and pyrocatechol. The calculations can accurately predict the substituent effects on the redox potentials of pyrocatechol and p -hydroquinone. We would expect that the accurate calculation results for the model systems could be applied in the prediction of electrode potentials of other molecules.
研究领域:
物理有机化学
·
电化学
·
计算化学
·
分子设计
·
生物电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2013
·Vol. 66
·期 1
·133-138
·
IF 1.66
Peng Shusen,Zhao Wenjie,Zeng Zhixiang,Li He,Xue Qunji,Wu Xuedong
In this report, hybrid silica sol–gel coating was prepared using Ce(NO 3 ) 3 (Sol-Ce) as catalyst. Structure, surface morphology and anticorrosion ability of Sol-Ce solution/coating were studied by infrared spectroscopy (IR), scanning electron microscopy, energy dispersive spectrometer (EDS), potentiodynamic scan (PDS) and electrochemical impedance spectroscopy (EIS). IR results showed that Ce(NO 3 ) 3 had a stronger influence on reactivity of alkoxysilane. EDS results revealed that the fraction of Fe in Sol-Ce coating was significantly lower than regular acid-catalyzed hybrid silica sol–gel coating (Sol-Ac) and Sol-Ac with Ce(NO 3 ) 3 -doped coating (Sol-Ac/Ce). The results of PDS and EIS demonstrated that Sol-Ce coating had better anticorrosion ability than Sol-Ac and Sol-Ac/Ce on carbon steel. The enhanced anticorrosion performance of the Sol-Ce coating might result from the following two reasons: (a) Ce(NO 3 ) 3 as a catalyst could alleviate the negative effects of low pH with using acid catalyst (dissolution of carbon steel) and (b) Ce(NO 3 ) 3 could impede corrosion of carbon steel as corrosion inhibitor.
研究领域:
材料科学
·
表面工程
·
腐蚀与防护
·
无机化学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 18
·
IF 1.768
Hongchuan Wu,Zhiguo Li,Libin Zhu,Jiyou Gu
Aqueous polyurethane micelles from 2,4,6-trichlorphenol blocking terminal-isocynate pre-polymer were prepared which could be de-blocked at low temperature. The prepared aqueous blocked polyurethane micelles (BPUMs) were uniform and spherical micro-particles. The particle size was decreased with increase of the DMPA content, while it was enlarged at first and then gradually decreased by increasing R -value. The stability of the micelles was affected by the R value, blocked efficiency and DMPA content. HDI-BPUMs were more stable than HDI-BPUMs at the same condition. The stability was further researched by the zeta potential combining with technique and viscosity tracking method, and the initial zeta potential be used as the stability criterion. In addition, a stabilization mechanism of the micelles was proposed. TCP-blocked TDI-BPUMs could be initially de-blocked at about 75°C and TCP-blocked HDI-BPUMs was de-blocked at about 80°C. The de-blocking temperature could be further reduced in the presence of catalyst, but it was scarcely affected by the change of R -value and DMPA content. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41908
研究领域:
高分子化学
·
胶体与界面科学
·
材料化学
·
功能材料
·
纳米材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）