RSC Advances
·
2015
·Vol. 5
·期 26
·20595-20602
·
IF 3.84
Genhua Wu,Chen Dong,Yonglong Li,Zhuqing Wang,Yuexia Gao,Zheyu Shen,Aiguo Wu
In this study, we propose a new silver nanoparticles (AgNPs)-based colorimetric sensor for rapid detection of Cu2+ or Mn2+ at pH 1.9 or 12.0, respectively. At pH 1.9, the AgNPs stabilized with sodium pyrophosphate (Na4P2O7) and hydroxypropylmethylcellulose (HPMC) gradually become smaller in the presence of Cu2+ resulting in a color change of the solution from yellow to colorless. At pH 12.0, however, the AgNPs aggregate immediately in the presence of Mn2+, which induces a color change of the solution from yellow to brown. The incubation time between the detection system and metal ion (Cu2+ or Mn2+) is fixed at 10 min. This mechanism is confirmed using UV-vis spectroscopy, Transmission electron microscopy (TEM), Dynamic light scattering (DLS) and Fourier-Transform Infrared Spectrometry (FT-IR). At the optimized experimental conditions, the selectivity of our AgNPs-based detection system is excellent for Cu2+ or Mn2+ compared with other metal ions. The limit of detections (LODs) of Cu2+ and Mn2+ by the naked eye are respectively 0.05 and 0.5 μM, and those by UV-vis spectroscopy are respectively 2.0 and 20 nM. The above LODs are all lower than the corresponding national drinking water standards (16 μM of Cu2+ and 1.8 μM of Mn2+). The applicability of our AgNPs-based colorimetric sensor is also validated by detection of Cu2+ and Mn2+ in tap water and lake water. Therefore, these results reinforce that our AgNPs-based colorimetric sensor is applicable to rapid colorimetric detection of Cu2+ and Mn2+ in complicated real water samples with excellent selectivity and high sensitivity.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 66
·61109-61118
·
IF 3.289
Baowen Sun,Chunsheng Wang,Shuhua Han,Yongfeng Hu,Lijuan Zhang
A silver nanocube (Ag NC) nanoparticle-enhanced fluorescent nanocomposite was developed. The designed nanocomposite contained an Ag NC core of 50 nm in size as enhancer, the 10 nm silica interlayer, and outer shell-periodic mesoporous organosilicas (PMOs) which incorporated the bis(rhodamine Schiff-base derivative) siloxane groups. Little fluorescence emission of nanocomposites was observed due to the existence of spirolactam in the rhodamine derivative, however, upon the addition of Cu2+, the fluorescence emission intensity increased dramatically, which resulted from ring-opening of the spirolactam in the rhodamine moieties. We showed the effect of using an Ag NC core on the fluorescence emission intensity of the novel system. The emission intensity was approximately 3-fold higher for Ag-nanocube@SiO2@PMOs than the control sample prepared by etching the silver core away with iodide. Moreover, the metal-enhanced fluorescence (MEF) mechanism in this system was investigated through measuring the fluorescence lifetime. In addition, the designed core–shell Ag-nanocube@SiO2@PMOs nanocomposite could act as a sensitive and selective sensor to detect the Cu2+, and we have been expecting that the detection limit would be reduced by reaping benefits from the plasmon resonance of Ag NC core in this nanocomposite system.
✓ 已验证
产品关联
DOI
高影响因子
NEW CARBON MATERIALS
·
2016
·
IF 0.993
Yue Wang,Wen-ting Wu,Ming-bo Wu,Hong-di Sun,Hui Xie,Chao Hu,Xue-yan Wu,Jie-shan Qiu
Yellow-visual fluorescent carbon quantum dots (CQDs) were prepared from petroleum coke by ultrasonic-assisted chemical oxidation and were used as label-free probes for Cu 2+ detection in water. The detection of Cu 2+ by CQD probes is related to a quenching of fluorescence by a photoinduced electron transfer mechanism. The quenched fluorescence of the CQDs by Cu 2+ can be recovered by adding ethylene diamine tetraacetic acid. The yellow-visual fluorescent CQD probes have a linear detection range from 0.25 to 10 μM, a detection limit of 0.0295 μM, a response time of 3 s, and a superior sensitivity and selectivity for Cu 2+ detection compared to other fluorescent probes. The CQDs are easy to prepare, economical, reusable, fast to respond and can be used in on-line detection.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2016
·
IF 5.886
Jian Sun,Bin Wang,Xue Zhao,Zong-Jun Li,Xiurong Yang
We demonstrate a rationally designed fluorescent and colorimetric dual-readout strategy for the highly sensitive, quantitative determination of inorganic pyrophosphatase (PPase) activity, a key hydrolytic enzyme involved in a variety of metabolic processes. Inspired by the selective oxidative and chromogenic reaction of o-phenylenediamine (OPD) with Cu2+, the special inhibitory effects of pyrophosphate (PPi) on the oxidative ability of Cu2+, and the specific hydrolysis of PPi into orthophosphate by PPase, a convenient small molecule OPD-based analytical system was developed for Cu2+/PPi recognition and PPase activity assay. We have confirmed that Cu2+ acts as the oxidant in the reaction and the main chromogenic product of OPD is 2,3-diaminophenazine (usually called OPDox) in the assay by combining the ESI-MS, 1H NMR, and XPS spectra analysis. Direct electrochemical insights into the Cu2+-triggered and PPi-inhibited mechanism were performed by cyclic voltammetry characterizations of the Cu2+ in the absence and presence of PPi for the first time. Furthermore, the proposed analytical system with clear response mechanism exhibits a promising outlook for the PPase activity assay in real biological samples and inhibitor screening.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Na Wang,Ying Liu,Yuhang Li,Qin Liu,Minqian Xie
In this paper, we propose a fluorescent and colorimetric sensor for Cu 2+ ion based on formaldehyde modified hyperbranched polyethylenimine capped gold nanoparticles (F-hPEI Au NPs). The fluorescent sensor is prepared by one-pot synthesis, of which the fluorescence intensity could be quenched by Cu 2+ ion. The response behavior of the sensor is dependent on the pH value of the solution. At pH 4.0, the sensor exhibits a linear response for Cu 2+ ion over a wide concentration range of 0.15 μM–23 μM. The detection limit for the sensor is estimated to be 77 nM (S/N = 3), and the precision for five replication detections of 2.0 μM Cu 2+ ion is 4.7% (relative standard deviation). Both the color and fluorescence intensity of the sensor change obviously and could be observed with the naked eyes when there is continuous addition of Cu 2+ ion. The fluorescence intensity of quenched sensor could be recovered by EDTA, which provides a potential method to regenerate the sensor. Furthermore, the sensor shows satisfying reliability and accuracy in practical Cu 2+ ion detection applications.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2017
·
IF 3.012
Shuo Duan,Yuming Huang
A novel electrochemical sensor was developed for the sensitive and selective detection of Cu 2 + , Pb 2 + and Cd 2 + , which was based on NH 2 -MIL-88(Fe)-rGO composite modified glass carbon electrode (NH 2 -MIL-88(Fe)-rGO/GCE). The NH 2 -MIL-88(Fe)-rGO composite was facilely prepared by a one-step method and characterized by SEM, XRD, Raman spectrum and electrochemical methods. The stepwise GCE modified process was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrochemical behaviors of Cu 2 + , Pb 2 + and Cd 2 + ions on the NH 2 -MIL-88(Fe)-rGO/GCE were explored by differential pulse anodic stripping voltammetry (DPASV). It was found that NH 2 -MIL-88(Fe)-rGO was capable of adsorbing Cu 2 + , Pb 2 + and Cd 2 + ions from aqueous solutions and the NH 2 -MIL-88(Fe)-rGO/GCE could enhance the electrochemical responses of Cu 2 + , Pb 2 + and Cd 2 + effectively. Important operational parameters such as electrolyte pH and deposition time were investigated and optimized for the determination of trace Cu 2 + , Pb 2 + and Cd 2 + ions. Under the optimum conditions, the proposed electrochemical sensor had a linear range of 0.005––0.3 μM for Cd 2 + , 0.01–0.3 μM for Pb 2 + and 0.005–0.05 μM for Cu 2 + , respectively. The limits of detection (LODs) are 4.9 nM for Cd 2 + , 10 nM for Pb 2 + and 3.6 nM for Cu 2 + , respectively. The proposed method has been successfully applied to determine three metal ions in water samples. The developed sensor promises simple preparation, fast operation, good sensitivity and excellent reusability, showing great potential for monitoring of water quality.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2013
·Vol. 1
·期 17
·5402-5407
·
IF 0
Chun Huang,Yan Chan,Fangyang Liu,Ding Tang,Jia Yang,Yanqing Lai,Jie Li,Yexiang Liu
Multicomponent chalcogenide Cu2(FexZn1−x)SnS4 nanocrystals were synthesized by a facile solution method. The ratio x of Fe/(Zn + Fe) can be tuned across the entire composition from 0 to 1 by rationally adjusting the Fe/Zn ratio in metal sources. By varying the value of x, the band gap energy of nanocrystals can be readily tuned from 1.25 eV to 1.52 eV. XRD analysis indicates the structure transition from stannite to kesterite may occur at x = 0.4 for Cu2(FexZn1−x)SnS4. In addition, photo-electrical conversion performance can be improved by partly substituting Zn with Fe in Cu2ZnSnS4.
✓ 已验证
产品关联
DOI
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Xianxiang Liu,Jiafu Xiao,Hui Ding,Wenzhou Zhong,Qiong Xu,Shengpei Su,Dulin Yin
Amino modified SBA-15 (SBA-NH 2 ) was used to immobilize vanadyl (VO 2+ ) and cupric (Cu 2+ ) ions, giving SBA-NH 2 -VO 2+ and SBA-NH 2 -Cu 2+ catalysts, respectively, and the as-prepared catalysts were characterized by XRD, XPS, TEM and Nitrogen adsorption–desorption technologies. The catalytic performance of the SBA-NH 2 -VO 2+ catalysts for the oxidation of HMF can be enhanced by the use of SBA-NH 2 -Cu 2+ as the co-catalyst. Several important reaction parameters were investigated, and it was found that the reaction solvent showed a great effect on the oxidation of HMF. The highest HMF conversion and product selectivity were obtained in aromatic solvents. The highest HMF conversion reached 98.8% at 110 °C in 4-chlorotoluene, affording DFF and 2,5-furandicarboxylic acid (FDCA) with yields of 28.9% and 62.7%, respectively. More importantly, the catalysts could be recycled and showed no significant decrease of their catalytic activities.
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2014
·Vol. 6
·期 17
·10289-10296
·
IF 6.739
Shao Qing Lie,Dong Mei Wang,Ming Xuan Gao,Cheng Zhi Huang
Copper chalcogenide nanocrystals (CuCNCs) as a type of semiconductor that can also act as efficient catalysts are rarely reported. Herein, we study water-soluble size-controlled Cu2−xSe nanocrystals (NCs), which are copper deficient and could be prepared by a redox reaction with the assistance of surfactants. We found them to have strong near-infrared localized surface plasmon resonance (LSPR) properties originating from the holes in the valence band, and also catalytic activity of more than a 500-fold enhancement of chemiluminescence (CL) in a luminol–H2O2 system. Investigations into the mechanisms behind these results showed that the high concentration of free carriers in Cu2−xSe NCs, which are derived from their high copper deficiencies that make Cu2−xSe NCs both good electron donors and acceptors with high ionic mobility, could greatly enhance the catalytic ability of Cu2−xSe NCs to facilitate electron-transfer processes and the decomposition of H2O2 into OH˙ and O2˙−, which are the commonly accepted key intermediates in luminol CL enhancement. Thus, it can be concluded that controllable copper deficiencies that are correlated with their near-infrared LSPR are critically responsible for the effective catalysis of Cu2−xSe NCs in the enhanced CL.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANICA CHIMICA ACTA
·
2013
·
IF 1.687
Peilun Yang,Baocun Zhu,Jie Zhao,Haiqin Yu,Liangguo Yan,Qin Wei,Bin Du
Recently, growing attention has been paid to the sensitive determination and removal of Cu 2+ because short-term exposure to high levels of Cu 2+ can cause gastrointestinal disturbance and long-term exposure can cause damage to the liver and kidneys. In this paper, we herein reported a novel reusable glutathione-modified magnetic fluorescent Fe 3 O 4 @ZnS nanosensor ( MFNS ) for simultaneous detection and removal of Cu 2+ from contaminated water samples. The results showed that MFNS could quantificationally detect Cu 2+ with high sensitivity and selectivity under a broad pH range (pH 4.6–9). The maximum sorption capacity of MFNS was calculated to be about 91 mg g −1 , which is superior to the reported reports. The removal of Cu 2+ from contaminated water samples was achieved by the aggregation-induced sedimentation (AIS) strategy. Moreover, the suspended magnetic nanosensor could be removed by external magnetic field, and the potential secondary pollution was avoided.
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2017
·Vol. 23
·期 46
·11037-11045
·
IF 5.317
Yuhao Xiong,Yuemei Qin,Linjing Su,Fanggui Ye
Graphical We report an efficient peroxidase mimic based on a copper-atom-modified covalent triazine framework (CCTF). Owing to its unique specific surface area, atomically dispersed active Cu sites, efficient electron transfer, and enhanced photo-assisted enzyme-like activity, the CCTF showed enhanced peroxidase-like enzyme activity. Therefore, copper modification presents an effective route to tailor the peroxidase-like activity of covalent triazine frameworks. Artificial enzymes is an emerging field of research owing to the remarkable advantages of enzyme mimics over their natural counterpart, including tunable catalytic efficiencies, lower cost, ease of preparation, and excellent tolerance to variations of the reaction system. Herein, we report an efficient peroxidase mimic based on a copper-modified covalent triazine framework (CCTF). Owing to its unique specific surface area, atomically dispersed active Cu sites, efficient electron transfer, and enhanced photo-assisted enzyme-like activity, the CCTF showed enhanced peroxidase-like enzyme activity. Therefore, copper modification represents an effective route to tailor the peroxidase-like activity of the covalent triazine frameworks. Furthermore, the mechanism of the enhanced peroxidase-like activity and stability of the CCTF were investigated. As a proof of concept, the CCTF was used for the colorimetric detection of H 2 O 2 and decomposition of organic pollutants. This work provides a new strategy for the design of enzyme mimics with a broad range of potential applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2024
·Vol. 20
·期 50
·2405908
·
IF 13
Lei Wang,Letu SiQin,Yiming Wang,Shuyu Li,Wenjing Xin,Jingyuan Guo,Ruijian Liu,Hongmei Luan,Chengjun Zhu
The Sol-gel precursor solution reaction mechanism has a significant impact on the Cu 2 ZnSn(S, Se) 4 (CZTSSe) solar cells. It is discovered that in the Cu 2 ZnSnS 4 (CZTS) precursor solution (CZTS-PS) in the preparation, there is an association reaction among Cu 2+ , thiourea (Tu), and carboxyl (-COOH), which is an important reason for the undesirable CZTSSe solar cells. The strong association reaction generates excessive Cu 2+ ions, forming the Cu x Se secondary phase on the surface of the CZTSSe absorber. The secondary phase causes a short circuit and deterioration of gadget performance. Following a 6-h aging period for the CZTS-PS, the average photoelectric conversion efficiency (PCE) of the device is enhanced to 8.02%, and there is also an improvement in device uniformity, as evidenced by a decrease in the standard deviation to less than 1. To inhibit the association reaction and eliminate the aging time phenomenon, a strategy is developed using hydrochloric acid to regulate the CZTS-PS environment. This strategy shifts the REDOX reaction in Cu 2+ +Sn 2+ toward the formation of Cu 1+ +Sn 4+ , leading to a decrease in the defect concentrations of V Sn (−/0) and Cu Sn (−/0), which increases the carrier concentration and reduces the impact of band tailing. The average power conversion efficiency (PCE) of the devices improved from 7.45% to 9.26%, the PCE of the best-performing CZTSSe solar cells increased from 9.25% to 9.83%, and the consistency among the devices is further enhanced, as indicated by a reduction in the standard deviation from 0.98 to 0.44. Ultimately, the device performance of the Cu 2+ +Sn 2+ -DMF system improved by 11.01% (without the MgF 2 layer) after optimization. This study serves as a reference for regulating the environment of the CZTS-PS to further enhance the CZTSSe devices' performance, and the photoelectric conversion efficiency is improved by ≈30%.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）