JOURNAL OF CHEMICAL PHYSICS
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2024
·Vol. 160
·期 20
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IF 3.1
Li Qingxia,Song Dongmei,Zhan Xinxing,Tong Xin,Hu Changgang,Tian Juan
Zeolitic Imidazolate Frameworks-8 (ZIF-8) is commonly used as an ideal precursor for non-noble metal catalysts because of its high specific surface area, ultra-high porosity, and N-rich content. Upon pyrolyzing ZIF-8 at 900 °C in Ar, the resulting material, referred to as Z 8 , displayed good activity toward the oxygen reduction reaction (ORR). Then the ZIF-8 was mixed with various conductive carbon materials, such as multiwall carbon nanotubes (MWCNTs), Acetylene black (ACET), Vulcan XC-72R (XC-72R), and Ketjenblack EC-600JD (EC-600JD), to form Z 8 composites. The Z 8 /MWCNTs composite exhibited enhanced ORR activity owing to its network structure, meso-/microporous hierarchical porous structure, improved electrical conductivity, and graphitization. Subsequently, iron and nitrogen co-doping is achieved through the pyrolysis of a mixture comprising Fe, N precursor, and ZIF-8/MWCNTs, which is denoted as FeN-Z 8 /MWCNTs. The intrinsically high electrical conductivity of MWCNTs facilitated efficient electron transfer during the ORR, while the meso-/microporous hierarchical porous structure and network structure of Fe, N co-doped ZIF-8/MWCNTs promoted oxygen transport. The presence of Fe-containing species in the catalyst acted as activity centers for ORR. This strategy of preparing Z 8 composites and modifying them with Fe, N co-doping offers an insightful approach to designing cost-effective electrocatalysts.
研究领域:
材料科学
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电化学
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Xinyue Liang,Xiaolong Yao,Sijie Chen,Wei Wang,Hong Zhu,Qingwei Bu,Zheng Liu
The highly toxic and recalcitrant organic pollutant, 2,4-dichlorophenol (2,4-DCP), is commonly found in wastewater. Therefore, it is critical to investigate novel techniques for the efficient removal of 2,4-DCP from wastewater. The present study employed a one-step synthesis method to fabricate ZIF-8/multi-walled carbon nanotubes (ZIF-8/MWCNTs) nanocomposites with well-defined mesoporous structures, which were subsequently coated onto carbon cloth (CC) to form the anode ZIF-8/MWCNTs/CC. Subsequently, the adsorption performance of ZIF-8/MWCNTs toward 2,4-DCP and the adsorption-electrochemical degradation performance of ZIF-8/MWCNTs/CC toward 2,4-DCP were investigated. ZIF-8/MWCNTs exhibit exceptional adsorption capacity and rate toward the 2,4-DCP. At 303 K, it achieved a saturated adsorption amount as high as 1056.78 mg·g - 1 within only 30 min of reaching equilibrium. Moreover, when coated on CC substrates, the internal pore structure of ZIF-8/MWCNTs is effectively exploited during the adsorption. In addition, the incorporation of MWCNTs enhances the conductivity of the ZIF-8/MWCNTs/CC electrodes, leading to reduced resistance and improved electron transfer rate. Notably, ZIF-8/MWCNTs/CC enabled complete removal of a 25 mg·L -1 solution of 2,4-DCP within only 90 min and a 50 mg·L -1 solution within 120 min. Furthermore, the degradation mechanism of 2,4-DCP was analyzed by means of DFT modeling theoretical calculations and intermediate product determination analysis, while evaluating the toxicity of the generated material was evaluated. This study provides improved solutions and strategies for the treatment of chlorophenolic compound pollution in wastewater.
研究领域:
环境科学
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材料科学
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化学工程
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水处理
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
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IF 4.65
Daile Zhang,Jianghua Zhang,Mingdi Pan,Yun Wang,Ting Sun
Electrochemical deposition is a facile technique to fabricate metal organic frameworks (MOFs) based materials in a short reaction time under mild conditions. In this work, novel necklace-like zeolitic imidazole framework@multiwalled carbon nanotubes (ZIF-8@MWCNTs) composite was synthesized by electrochemical method for the first time and then used as precursor for subsequent carbonization and acid treatment. The resultant porous carbon material (C-ZIF-8@MWCNTs) maintained the necklace-like structure with a high surface area of 1063.2 m 2 g −1 . When used as electrode material for supercapacitor , the C-ZIF-8@MWCNTs demonstrated a high specific capacitance of 259.2 F g −1 at the current density of 0.5 A g −1 . Further, the capacitance retention could reach 92% after 5000 cycles under the current density of 15 A g −1 . Due to the large specific surface area of the porous carbon derived from ZIF-8 and the intrinsic high conductivity, the C-ZIF-8@MWCNTs displayed good rate ability and cycle performance. The current work can expand the method to synthesize functional MOFs-based materials for advanced applications.
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 THE ELECTROCHEMICAL SOCIETY
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2024
·Vol. 171
·期 4
·047514
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IF 3.1
Xuemei Ma,Wanyu Pang,Yali Gao,Xile Chang,Zhiyong Hu,Tuoping Hu
Rapid and accurate determination of rutin content in pharmaceuticals in an important issue. Here, a paper-based electrochemical sensor for in situ growth of chain ZIF-8 using multi-walled carbon nanotubes (MWCNTs) as a template was constructed by hydrothermal method. The results showed that the combination of ZIF-8 and MWCNTs not only promoted the dispersion of MWCNTs, but also made up for the conductivity of ZIF-8. Under optimum conditions, the Ipa was linearly related to the concentration of rutin in the range of 0.01–10 and 10–190 μM with a limit of detection (LOD) of 2.82 nM. Finally, the paper-based electrochemical sensor can be used for the electrochemical detection of rutin through the determination of rutin in pharmaceuticals.
研究领域:
分析化学
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材料科学
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药学
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DOI
高影响因子
Analytical Methods
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2024
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IF 2.7
Zhiren Zhou,Yuting Tian,Lina Zou,Yanan Liu,Xueqing Zhang,Xiaojing Huang,Huanyu Ren,Zheng Li,Huiru Niu,Hao Liao,Xiaojing Zhang,Hongzhi Pan,Shengzhong Rong,Hongkun Ma
Nuclear matrix protein 22 (NMP22) is one of the most important tumor markers of bladder cancer and is significantly elevated in the urine of bladder cancer patients. Therefore, in this work, a highly sensitive ratiometric electrochemical immunosensor was constructed to detect NMP22 based on ZIF-8@MWCNTs@Chit@Fc@AuNPs composites. ZIF-8 had a large surface area and good adsorption ability. Multi-Walled Carbon Nanotubes (MWCNTs) can optimize the electrical conductivity of ZIF-8, so that the electrode surface of ferrocene (Fc) obtains a stable and strong electrochemical signal. In addition, AuPt-MB provided another strong detection signal methylene blue (MB) while immobilizing the secondary antibody (Ab2) through Au–N and Pt–N bonds. A ratiometric electrochemical sensor was formed based on ZIF-8@MWCNTs@Chit@Fc@AuNPs and AuPt-MB, which showed a great linear connection between IMB/IFc and the logarithmic concentration of NMP22 with a detection limit of 3.33 fg mL−1 (S/N = 3) under optimized specifications in the concentration interval of 0.01 pg mL−1 to 1000 ng mL−1. In addition, the ratiometric immunosensor showed good selectivity and stability.
研究领域:
生物医学工程
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肿瘤学
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分析化学
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DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Xinyue Liang,Weihong Zhang,Xiaolong Yao,Zhengyang Feng,Qingwei Bu,Wenwen Gong,Wei Wang,Chun Wang,Yingxue Sun
Adsorption-electrocatalytic oxidation is a promising technology for organochlorine removal; however, its practical application is hindered by electrode limitations in activity, stability, and mechanistic understanding. In this study, a copper-doped ZIF-8/multi-walled carbon nanotube composite electrode (Cu-ZIF-8/MWCNTs/CC) was innovatively designed. Adsorption-electrochemical batch experiments were conducted to systematically investigate the degradation behaviors of three typical organochlorine contaminants: 2,4-dichlorophenol (2,4-DCP), triclosan (TCS), and chloramphenicol (CAP), using MOF-based electrodes. The results demonstrate that compared to the undoped ZIF-8/MWCNTs/CC, the incorporation of Cu introduced additional mesoporous structures and Cu-N coordination bonds, which effectively enhanced adsorption performance based on the size-matching effect and d-band center theory. Furthermore, the highly reversible and kinetically rapid Cu 2 + /Cu + redox couple served as an efficient mediator for charge transfer, thus promoting the synergistic adsorption and electrochemical degradation of organochlorine contaminants. Notably, the material maintained considerable removal efficiency even under competitive conditions in multicomponent systems. Mechanistic investigation demonstrated that hydroxyl radicals (·OH) preferentially attacked critical chemical bonds (including C-Cl, ether, and amino groups) in accordance with density functional theory (DFT) predictions. This reaction pathway resulted in the generation of less toxic intermediates that were eventually mineralized into CO 2 and H 2 O. The ecological structure-activity relationships (ECOSAR) model further confirmed the low acute and chronic toxicity of the major degradation products. Moreover, the electrode maintained high removal efficiency across multiple consecutive cycles, demonstrating excellent stability and reusability. Collectively, this work proposes a novel strategy for the synergistic adsorption and electrocatalytic removal of organochlorine contaminants; thereby highlighting its significant potential for practical application.
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高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2022
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IF 6.76
Xinling Zhang,Ning Yuan,Shuo Xu,Yi Li,Qibao Wang
The removal of organic pollutants was examined by new zeolitic imidazolate framework-8/carboxyl-functionalized multi-walled carbon nanotubes (ZIF-8/MWCNTs-COOH) nanoadsorbents, which were prepared via controlling the reaction sequence of MWCNTs-COOH with the precursors of ZIF-8. Structural morphology and chemical composition characterizations confirmed the successful preparation of ZIF-8/MWCNTs-COOH nanoadsorbents. The obtained samples manifested a preferable adsorption capacity for Congo red with the maximum adsorption capacity of 1185.58 mg g −1 with an adsorption removal rate of 97.93% at equilibrium adsorption. Further analyses indicated that the adsorption process conformed to the pseudo-second-order kinetic model and Langmuir adsorption isotherm. The thermodynamic analyses were depicted as endothermic, entropy-increasing, and spontaneous. The effects of pH value, interfering ions, and dosage on the adsorption properties were systematically explored. The nanoadsorbent can be expediently reused for eight cycles without a prominent reduction in adsorption activity. The improved performance and high reusability can be ascribed to the increasing specific surface, the presence of electrostatic interaction, hydrogen bonding, and π–π interaction between ZIF-8/MWCNTs-COOH and organic molecules. In addition, the prepared composites also showed a better adsorption performance for tetracycline with the equilibrium adsorption capacity of 471.22 mg g −1 compared to pure ZIF-8 and MWCNTs-COOH.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
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