MOLECULES
·
2019
·Vol. 24
·期 17
·3041
·
IF 3.06
Yanqing Liu,Gengxin Hu,Hongwu Wang,Su Yao,Yinjian Ye
A hybrid nanocomposite consisting of hydroxylated multi-walled carbon nanotubes (MWCNTs−OH) and cube mesoporous carbon (CMK−8) was applied in this study to construct an MWCNT−OH/CMK−8/gold electrode (GE) electrochemical sensor and simultaneously perform the electro-reduction of olaquindox (OLA) and carbadox (CBX). The respective peak currents of CBX and OLA on the modified electrode increased by 720- and 595-fold relative to the peak current of GE. The performances of the modified electrode were investigated with electrochemical impedance spectroscopy, cyclic voltammetry, and differential pulse voltammetry. Then, the modified electrodes were used for the individual and simultaneous determination of OLA and CBX. The fabricated sensor demonstrated a linear response at 0.2–500 nmol/L in optimum experimental conditions, and the detection limits were 104.1 and 62.9 pmol/L for the simultaneous determination of OLA and CBX, respectively. As for individual determination, wide linear relationships were obtained for the detected OLA with levels of 0.05–500 nmol/L with LOD of 20.7 pmol/L and the detected CBX with levels of 0.10–500 nmol/L with LOD of 50.2 pmol/L. The fabricated sensor was successfully used in the independent and simultaneous determination of OLA and CBX in spiked pork samples.Keywords:CMK−8;MWCNTs−OH;electrochemical sensor;differential pulse voltammetry;simultaneous determination;carbadox;olaquindox
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Xiaoxiang Cheng,Weiwei Zhou,Daoji Wu,Congwei Luo,Ruibao Jia,Peijie Li,Lu Zheng,Xuewu Zhu,Heng Liang
In this study, ordered mesoporous carbons (OMCs), i.e., CMK-3 and CMK-8 were pre-deposited on ultrafiltration membrane surface to alleviate membrane fouling by organic matter in the water. CMK-3 shows a typical 2D hexagonal symmetrical structure with long straight parallel channels, while CMK-8 exhibits a 3D porous structure with cubic channels. The pre-deposited CMK-3/CMK-8 layers exhibited significantly superior performance for both flux enhancement and fouling mitigation, whereas powdered activated carbon (PAC) showed limited influence. The fouling mechanism was apparently altered by the OMCs pre-deposition layers, and pore blocking always dominated throughout the filtration process without the formation of cake filtration. In comparison with PAC, CMK-3 and CMK-8 were more effective for the rejection of tryptophan-like protein substances, which were the major foulants causing membrane fouling. The effects of pollutant fraction and deposited amount (i.e., 6, 12, 25 and 50 g/m 2 ) were systematically explored, and the results indicated that this technology was more efficient for alleviating the fouling induced by humic acid and bovine serum albumin, whereas ineffective for sodium alginate fouling, and the optimal deposited amount varied with the pollutant fraction. CMK-3 exhibited significantly superior performance than CMK-8, likely due to its long straight parallel channels with lower internal resistance for pollutants adsorption. Both adsorption and size exclusion of the pre-deposited layers contributed to fouling mitigation. These results demonstrate that pre-depositing with OMCs as alternatives to conventional PAC shows promising potential for mitigating membrane fouling in water treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 15
·4954
·
IF 4.927
Chengqi Bao,Yan Lu,Jiawei Liu,Yansha Gao,Limin Lu,Shuwu Liu
In this work, β-cyclodextrin (β-CD)/mesoporous carbon (CMK-8) nanocomposite was synthesized and used as an electrochemical sensing platform for highly sensitive and selective detection of Cu2+. The morphology and structure of β-CD/CMK-8 were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). In addition, the dates from electrochemical impedance spectroscopy (EIS) and Cyclic voltammetry (CV) demonstrated that the β-CD/CMK-8 possessed a fast electronic transfer rate and large effective surface area. Besides this, the β-CD/CMK-8 composite displayed high enrichment ability toward Cu2+. As a result of these impressive features, the β-CD/CMK-8 modified electrode provided a wide linear response ranging from 0.1 ng·L−1to 1.0 mg·L−1with a low detection limit of 0.3 ng·L−1. Furthermore, the repeatability, reproducibility and selectivity of β-CD/CMK-8 towards Cu2+were commendable. The sensor could be used to detect Cu2+in real samples. All in all, this work proposes a simple and sensitive method for Cu2+detection, which provides a reference for the subsequent detection of HMIs.Keywords:copper ion;β-cyclodextrin;mesoporous carbon;electrochemical sensor
研究领域:
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Xiaoxiang Cheng,Peijie Li,Xuewu Zhu,Congwei Luo,Lu Zheng,Chengsi Hou,Daoji Wu,Heng Liang
In this study, carbon nanoparticles (CNPs) in different structural dimensions, including carbon nanotubes (CNTs), carbon nanofibers (CNFs), hexagonally (CMK-3) and cubically (CMK-8) ordered mesoporous carbons were proposed for peroxymonosulfate (PMS) activation. The performance for catalytic oxidation of organic pollutants and alleviating ultrafiltration membrane fouling was systematically investigated and compared. The results showed that CMK-3 performed best for PMS activation in the reduction of typical micropollutants and natural organic matter, whereas the efficiency of CNFs was relatively limited. The CNPs/PMS processes were efficient alternatives for alleviating membrane fouling, whereas discrepancies existed in the performance for different CNPs. Both the decomposition of macromolecular biopolymers and the degradation of fluorescent components reduced the foulants directly contacting with membranes, thus contributing to the fouling mitigation. The characterization of fouled membranes (i.e., surface morphologies and functional groups) further verified the fouling alleviation. From a comparison view, the decomposition of PMS by CMK-3 was more effective compared to the other CNPs, with the catalytic capacity of CMK-3 > CNTs > CMK-8 > CNFs. The discrepancy was likely ascribed to the microstructure differences of carbonaceous materials. To be specific, CNTs exhibited a curled-like shape with smaller diameter and larger specific surface area than CNFs, while CMK-3 showed long straight and parallel channels with decreased internal resistances than CMK-8. The electron paramagnetic resonance analyses revealed that SO 4 − , OH, O 2 − and 1 O 2 were the main reactive oxygen species generated in the systems. The CNPs/PMS processes significantly changed the fouling mechanisms by delaying the formation of cake layers and prolonging the transition volumes. These findings possess a guiding significance for the application of carbon-based catalytic oxidation in membrane water treatment processes.
研究领域:
环境科学
·
水处理
·
纳米技术
·
催化
✓ 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）