APPLIED CATALYSIS A-GENERAL
·
2018
·
IF 4.521
Zihao Zhang,Changxue Wang,Xin Gou,Hao Chen,Kequan Chen,Xiuyang Lu,Pingkai Ouyang,Jie Fu
A series of Cu-based catalysts with different supports were synthesized and studied for the in situ hydrogenation of 5-hydroxymethylfurfural (5-HMF) to dimethylfuran (DMF) using methanol as an economical hydrogen donor. The structures and properties of the four catalysts (Cu/Al 2 O 3 , Cu/ZnO, Cu/ZrO 2 , and Cu/CeO 2 ) were characterized using X-ray diffraction (XRD), temperature-programmed reduction (H 2 -TPR), and temperature-programmed desorption of ammonia (NH 3 -TPD). The experimental results showed that the use of different supports for the Cu-based catalysts significantly influenced their activity for both H 2 production from methanol and hydrogenation of 5-HMF. The catalyst Cu/Al 2 O 3 showed the best catalytic activity, which can be attributed to the highest activity for the in situ H 2 production from methanol, smallest Cu crystallite size, and strongest acidity. The effects of the substrate concentration, catalyst loading, and reaction temperature and time on the in situ hydrogenation of 5-HMF were systematically investigated to determine the optimum reaction conditions.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Liuting Mo,Huiwen Pang,Yi Tan,Shifeng Zhang,Jianzhang Li
The utilization of easily recyclable biosorbent material with ultrahigh adsorption capacity for the removal of heavy metal ions from aqueous environments is an important step towards eradicating water pollution worldwide. In this study, a novel amino-functionalized nanocellulose aerogel adsorbent for efficient and reversible recycle capture of Cu(II) ions was fabricated via self-assembly of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized cellulose nanofibril (TO-CNF) crosslinked Trimethylolpropane-tris-(2-methyl-1-aziridine) propionate (TMPTAP) and polyethyleneimine (PEI). The TO-CNF was spontaneously reacted with TMPTAP via a ring-opening reaction in an aqueous solution at room temperature and then cross-linked with PEI. The resultant TO-CNF/TMPTAP/PEI aerogel showed a 3D multi-wall perforated cellular structure with plentiful amino groups and oxygen-containing groups. The unique architecture of the TO-CNF/TMPTAP/PEI aerogel allowed an ultrahigh Cu(II) ion adsorption capacity of 485.44 mg/g as-calculated by the Langmuir isotherm model, which is almost the highest value among known biodegradable cellulose-based adsorbents. The TO-CNF/TMPTAP/PEI aerogels also can restore their original architecture after regeneration by EDTA-2Na treatment and be utilized more than four cycles without significant degradation of adsorption performance. The ultrahigh adsorption capacity, good recyclability and reversibility, excellent chemical and structural stability, and ease of separation make these composite aerogels ideal materials for the adsorption of Cu(II) ions in practical wastewater treatment applications.
✓ 已验证
产品关联
DOI
高影响因子
Energy Technology
·
2018
·Vol. 7
·期 8
·1800846
·
IF 3.175
Sibo Chen,Siyuan Yang,Xiaolin Sun,Kelin He,Yun Hau Ng,Xin Cai,Wuyi Zhou,Yueping Fang,Shengsen Zhang
The photocatalytic H 2 evolution is an important technology to solve the energy crisis. The hydrogen evolution rate of the graphite carbon nitride (g-C 3 N 4 ) system in triethanolamine solution as sacrificial agent is clearly higher than that in methanol solution. But up to now, most of the Cu nanoparticles as cocatalyst of g-C 3 N 4 photocatalytic systems for hydrogen evolution are performed in methanol solution because Cu nanoparticles are unstable in triethanolamine solution. Here, carbon-coated Cu nanoparticles as a cocatalyst of g-C 3 N 4 composites (Cu@C/g-C 3 N 4 ) are prepared by a simple two-step technology that includes annealing followed by grinding. The compositions, morphology, and optical and photoelectrochemical properties of the composites are characterized by means of physicochemical techniques. The prepared composition is used to generate hydrogen under visible-light irradiation in triethanolamine solution. The results show that the hydrogen evolution rate of the optimal Cu@C/g-C 3 N 4 is up to 265.1 μmol g −1 h −1 , which is close to the activity of 0.5% Pt/g-C 3 N 4 , and after four repeated reactions, the photocatalytic activity decreases only by ≈15%. The good photocatalytic activity and stability result from Cu nanoparticles increase the transfer efficiency of charge carriers by trapping the photogenerated electrons produced by g-C 3 N 4 and the protective effect of carbon layer on Cu nanoparticles.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Yu-Xia Li,Yu-Nong Ji,Meng-Meng Jin,Shi-Chao Qi,Shuai-Shuai Li,Ding-Ming Xue,Ming Bo Yue,Xiao-Qin Liu,Lin-Bing Sun
Here, we designed a double-solvent/host–guest redox combined strategy to construct Cu+ sites in metal–organic frameworks (MOFs) for the first time. As a proof of concept, a representative MOF MIL-100(Fe) with tunable valence states of cations was employed as the host. The combined strategy realizes selective introduction of Cu2+ precursors to the interior pores of MIL-100(Fe), remarkably minimizing the aggregation of Cu2+ and subsequently formed Cu+ species. Owing to the proper reducibility of in situ formed Fe2+ in the frameworks, controlled conversation of Cu2+ to Cu+ with ∼100% yield is achieved in the absence of any additional reducing agents. These characteristics make the obtained materials Cu+-modified MIL-100(Fe) highly active in selective CO adsorption. The CO adsorption capacity is up to 3.75 mmol·g–1 at 298 K and 1 bar, which is superior to all other Cu+-containing adsorbents reported so far such as CuCl/activated carbon (2.5 mmol·g–1), CuCl/γ-Al2O3 (1.0 mmol·g–1), and CuCl/SBA-15 (0.50 mmol·g–1). The same adsorbent also exhibits quite high selectivity of CO over N2, and the ideal adsorption solution theory selectivity reaches 424. The outstanding CO adsorption performance make the present adsorbents great potential in separation of CO from various mixtures.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 19
·10635-10644
·
IF 3.049
Xiaoxu Xuan,Jun Cheng,Xiao Yang,Junhu Zhou,Kefa Cen
Carbon supported nano-metal catalysts are expected to improve CO2 reduction selectivity and efficiency due to the addition of more active sites and enhancement of electron transport ability. In this study, HKUST-1 was pyrolyzed and decorated with Pt to prepare Pt–Cu/C catalysts. The catalytic effect of the catalysts with different Pt contents in the CO2 photoeletrochemical reduction reaction (CO2PRR) were compared. The total carbon atom conversion rate in CO2PRR experiments using Pt–Cu/C catalysts first increased to a peak when using 1.6 wt% Pt–Cu/C catalyst and then decreased with the increase of Pt content. The 1.6 wt% Pt–Cu/C catalyst showed good hydrogen evolution reaction (HER) inhibiting ability compared with other Pt–Cu/C catalysts. Density functional theory (DFT) calculations were conducted to give an insight into the CO2PRR mechanism on some possible active sites in Pt–Cu/C catalysts. The result demonstrated that HER was more likely to be inhibited on the Cu/Pt active surface and at the same time CO2PRR was promoted.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2019
·
IF 7.149
Xiaolin Zhang,Ping Huang,Siyao Zhu,Ming Hua,Bingcai Pan
Toxic metals are usually present as organic complexes in high-salinity effluents from various industries. The efficient removal of such metal complexes is an imperative but still challenging task due to their stable structure and high mobility. Herein, we propose a new strategy to remove Cu-carboxyl complexes from high-salinity water by using a commercially available nanocomposite HZO-201, i.e., nanohydrated zirconium oxide (HZO) confined inside anion exchanger D201. In contrast to D201 and a cation exchanger D001, which both adsorb Cu-citrate negligibly, HZO-201 exhibits preferable adsorption toward Cu-citrate (∼130 mg Cu/g-Zr) at high salinity (1.5 wt % NaCl). On the basis of scanning transmission electron microscopy energy-dispersive spectrometry (STEM-EDS), attenuated total reflection Fourier transform infrared (ATR-FTIR), and X-ray photoelectron spectrometry (XPS) analysis, the formation of ternary complex among Cu(II), citrate, and the embedded nano-HZO is evidenced to be responsible for the removal of Cu-citrate. The exhausted HZO-201 can be regenerated with a binary HCl-NaCl solution for repeated use for 5 cycles without capacity loss. Fixed-bed adsorption demonstrates that HZO-201 column is capable of producing ∼1150 bed volume (BV) clean water (<0.5 mg Cu/L) from simulated high-salinity wastewater, whereas only ∼10 BV and ∼60 BV was produced for the D001 and D201 columns, respectively. Furthermore, HZO-201 shows excellent removal of Cu(II) complexes with three other carboxyl ligands (oxalate, tartrate, and succinate).
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRIBOLOGY INTERNATIONAL
·
2019
·
IF 3.517
Zhenqi Guo,Yujuan Zhang,Jucai Wang,Chuanping Gao,Shengmao Zhang,Pingyu Zhang,Zhijun Zhang
This work was to investigate the interactions of Cu NPs with dispersant , detergent, antioxidant, friction modifier , viscosity index improver on tribological performance and some physicochemical properties of diisooctylsebacate (DIOS). The results indicate that Cu NPs and most additives have a synergy on tribological performance. Whereas, Cu NPs and dispersant or detergent can only enhance wear resistance. When phenols antioxidant, viscosity index improver and ZDDP are added together with Cu NPs, the antioxidation performance of DIOS can be distinctly improved. Nevertheless, amines antioxidant and Cu NPs exhibit antagonistic effect. The kinematic viscosity of DIOS can be enhanced by adding viscosity index improver together with Cu NPs. The synergetic effects between ZDDP/MoDTC and Cu NPs are both obvious in many properties.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2018
·
IF 6.042
Xiangying Yu,Man-Chu Chau,Wai Kit Tang,Chi-Kit Siu,Zhong-Ping Yao
Naproxen is one of the most consumed nonsteroidal anti-inflammatory drugs and marketed as S-naproxen since R-naproxen is hepatotoxic. In this study, chiral recognition of naproxen has been investigated by tandem mass spectrometry (MS/MS). Among all diastereomeric complexes formed between naproxen and the examined chiral selectors, including cyclodextrins (α/β/γ-CD), modified phenylalanines (N-acetyl-phenylalanine, N-t-butoxycarbonyl-phenylalanine, N-9-fluorenylmethyloxycarbonyl-phenylalanine), amino acids (Trp, Phe, Tyr, His), glucose, tartaric acid, and vancomycin, a novel binuclear metal bound diastereomeric complexes [(M(II))2(S/R-naproxen)(l-His)2−3H]+ (M = Cu, Ni, or Co with Cu being the best) could allow effective identification of the absolute configuration of naproxen and determination of its enantiomeric excess (ee) through MS/MS analysis. The key candidate structure of [(Cu(II))2(S/R-naproxen)(l-His)2−3H]+ has been revealed by means of collision-induced dissociation, ion mobility mass spectrometry and density functional theory calculations, indicating an interesting and unusual self-assembled compact geometry with the two Cu(II) ions bridged closely together (Cu–Cu distance is 3.04 Å) by the carboxylate groups of the two histidines. It was shown that the difference in dissociation efficiency between the two diastereomers was attributed to the interaction between the NH2 bond of the amino group of one histidine and the naphthyl ring of naproxen. The present report is the first to observe and characterize the complex of (Cu(II))2(His)2 with aromatic acid, which could contribute to the chiral recognition of other chiral aromatic acids, design of catalysts based on binuclear copper bound complex, as well as the better understanding of metal ion complexation by His or His-containing ligands.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2018
·
IF 4.244
Nuanfei Zhu,Yanmin Zou,Menglu Huang,Shuaibing Dong,Xiangyang Wu,Guoxi Liang,Zhixiang Han,Zhen Zhang
A sensitive and artful colorimetric immunosensor based on horseradish peroxidase (HRP) was designed by labelling metal–organic frameworks (Cu-MOFs) on the second antibody (Cu-MOFs@Ab 2 ) as signal amplification for the detection of trace dibutyl phthalate (DBP). In this system, when Cu-MOFs@Ab 2 was captured by antigen- primary antibody (Ab 1 ) complex, tremendous Cu(II) will be released from Cu-MOFs in the presence of nitric acid (HNO 3 ), and Cu(II) will be further reduced to Cu(I) after the addition of sodium ascorbate (SA), consequently, inhibiting the HRP to catalyse the colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into blue oxidized TMB (ox TMB). Under the optimized conditions, the limit of detection (LOD) was 1 μg L −1 , which was almost 60 times lower than that using a conventional ELISA with the same antibody. In addition, our method showed good accuracy and reproducibility (recoveries of 87.73–103.4%; CV values of 1.46–5.95%) through a spike-recovery analysis. The proposed immunosensor indicated great potential for trace DBP determination from environmental and food samples.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 5
·1-9
·
IF 5.705
Han Xiujuan,Meng Zuchao,Zhang Hongfang,Zheng Jianbin
Various carbon nanomaterials for use in anodic stripping voltammetric analysis of Hg(II), Cu(II), Pb(II) and Cd(II) are screened. Graphene, carbon nanotubes, carbon nanofibers and fullerene (C 60 ), dispersed in chitosan (Chit) aqueous solution, are used to modify a glassy carbon electrode (GCE). The fullerene-chitosan modified GCE (C 60 -Chit/GCE) displays superior performance in terms of simultaneous determination of the above ions. The electrodes and materials are characterized by electrochemical impedance spectroscopy, cyclic voltammetry, scanning electron microscopy, Raman spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The excellent performance of C 60 -Chit/GCE is attributed to the good electrical conductivity, large surface area, strong adsorption affinity and unique crystalline structure of C 60 . Using differential pulse anodic stripping voltammetry, the assay has the following features for Hg(II), Cu(II), Pb(II) and Cd(II), respectively: (a) Peak voltages of +0.14, −0.11, −0.58 and − 0.82 V (vs SCE); (b) linear ranges extending from 0.01–6.0 μM, 0.05–6.0 μM, 0.005–6.0 μM and 0.5–9.0 μM; and (c), detection limits (3σ method) of 3 nM (0.6 ppb), 14 nM (0.9 ppb), 1 nM (0.2 ppb) and 21 nM (2.4 ppb). Moreover, the modified GCE is well reproducible and suitable for long-term usage. The method was successfully applied to the simultaneous determination of these ions in spiked foodstuff.
Compared with graphene, carbon nanotubes and carbon nanofibers, an electrode modified with fullerene in chitosan electrode displays superior performance for the simultaneous anodic stripping voltammetric detection of Hg(II), Cu(II), Pb(II) and Cd(II).
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Ying Liu,Deli Wu,Shuhan Peng,Yong Feng,Zhigang Liu
Cu-Fe-O nanoparticles (CFO NPs), synthesized with zero-valent iron (ZVI) and Cu(NO 3 ) 2 as the metal precursors, were used to enhance ozonation to degrade dimethyl phthalate (DMP). Great DMP degradation and mineralization rates were achieved in a wide range of the initial pH values (3–9); the amount of OH in catalytic ozonation was much higher than that of O 3 alone at the initial pH of 5.70. The generation of hydroxyl radicals ( OH), methyl radicals ( CH 3 ) and superoxide radicals (O 2 − ) were identified and OH mainly contributed to DMP removal. The potential of Fe(III)/ Fe(II) and Cu(II)/ Cu(I) cycles have largely been overlooked, which was found to be the key for producing more OH in CFO/O 3 system. The underlying mechanisms were probably initiated by a chain reaction: initiated O 3 reaction with Cu(I)/ Fe(II) OH to form OH and O 2 − , accelerated reaction between Cu(II)/ Fe(III) and the in situ generated O 2 − with a relatively high reaction constant, redox reaction between Cu(I) and Fe(III), OH oxidizing reaction with DMP to produce CH 3 . In addition, different degradation pathways of DMP were proposed based on the intermediates in the presence of CH 3 . This study sheds new light on the specific radical chain reaction mechanisms of catalytic ozonation.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Wanbing Gong,Chun Chen,Haimin Zhang,Guozhong Wang,Huijun Zhao
Herein, we report that highly dispersed copper–cobalt mixed metal/metal oxide nanoparticles embedded into three-dimensional porous carbon were highly catalytic active nanocomposites for transforming bioderived furfural (FAL) to cyclopentanone (CPO) via aqueous-phase hydrogenation/rearrangement. This simple and efficient catalyst was prepared by controlled pyrolysis procedure using glucose as the carbon source at 500 °C under N2 atmosphere. Characterization of the as-prepared CuCo0.8@C-500 catalyst by XRD, STEM, SEM, TEM, and XPS suggested that there was a synergism between copper and cobalt. Under an extremely low H2 pressure (0.5 MPa), 90.2% yield of CPO could be attained at 150 °C. In addition, the sample could be recycled for several times without decrease in catalytic activity. Two critical reaction intermediates of furfuryl alcohol (FOL) and 2-cyclopentenone (2-CPE) were detected in the tandem catalytic process. These results demonstrated that this synthetic strategy represented a simple and effective way for utilization of inexpensive biomass resources to obtain some valuable chemicals.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）