APPLIED ORGANOMETALLIC CHEMISTRY
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2020
·Vol. 34
·期 10
·e5814
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IF 3.14
Yongcen Lin,Xue Dong,Lang Zhao
N-ZIF-(1:0)@NiCo-LDH, N-ZIF-(1:3.5)@NiCo-LDH and N-ZIF-(0:1)@NiCo-LDH were prepared by mixing solvents in various volume ratios ( V methanol : V water = 1:0, 1:3.5 and 0:1) when synthesizing precursors. These composite materials were characterized using scanning and transmission electron microscopies, X-ray diffraction, X-ray photoelectron spectroscopy and nitrogen adsorption–desorption measurements, and investigated as catalysts for reduction of 4-nitrophenol, methyl orange and methylene blue. The NaBH 4 concentration as an important factor that may affect catalytic activity for reduction of 4-nitrophenol was examined. Under optimal experimental conditions, the excellent catalytic activity of the N-ZIF-(0:1)@NiCo-LDH composite, compared to that of N-ZIF-(1:0)@NiCo-LDH and N-ZIF-(1:3.5)@NiCo-LDH composites, could be attributed to the presence of graphitic nitrogen. In addition, compared with previously reported catalysts, all catalysts prepared show excellent catalytic activity owing to the unique structure exposing more active sites.
研究领域:
材料科学
·
环境化学
·
催化化学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 23
·8572
·
IF 4.927
Wanning Xiong,Jie Ouyang,Xiaoman Wang,Ziheng Hua,Linlin Zhao,Mengyao Li,Yuxin Lu,Wei Yin,Gonggang Liu,Cui Zhou,Yongfeng Luo,Binghui Xu
Transition metal oxides (TMOs) can provide high theoretical capacitance due to the change of multiple valence states of transition metals. However, their intrinsic drawbacks, including poor electrical conductivity, lower energy density, and huge volume expansion, will result in the pulverization of electrode materials and restricted electrochemical kinetics, thus leading to poor rate capability and rapid capacity fading. Composite electrodes based on transition metal oxides and carbon-based materials are considered to be promising candidates for overcoming these limitations. Herein, we reported a preparation method of hybrid ZIFs derived Zn-doped Co3O4/carbon (Zn-Co3O4/C-230) particles semi-embedded in wood-derived carbon skeleton for integrated electrodes. A large specific surface area, excellent conductivity, and electrochemical stability provide a larger electrochemical activity and potential window for the electrode. Prepared Zn-Co3O4@CW-230 electrode (0.6 mm thick) displays ultrahigh area specific capacitances of 7.83 and 6.46 F cm−2at the current densities of 5 and 30 mA cm−2, respectively. Moreover, a symmetric supercapacitor assembled by two identical Zn-Co3O4@CW-230 electrodes delivers a superior area-specific capacitance of 2.61 F cm−2at the current densities of 5 mA cm−2and great energy densities of 0.36 mWh cm−2(6.0 mWh cm−3) at 2.5 mW cm−2, while maintaining 97.3% of initial capacitance over 10,000 cycles. It notably outperforms those of most carbon-based metal oxides, endowing the Zn-Co3O4@CW-230 with extensive prospects for practical application.Keywords:semi-embedding;transition metal oxides;hybrid ZIFs;wood-derived carbon;supercapacitors
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2023
·
IF 5.3
Junhui Liu,Bing Li,Mengting Li,Yuan Hu,Shan Han,Xinwen Guo
Transformation of abundant and economical feedstock CO2 and renewable H2 into valuable hydrocarbons is considered a prospective route for the storage of renewable energy. However, it is also a challenge to prepare highly stable and active catalysts. Herein, active and stable catalysts were designed by pyrolysis of the Fe-modified bimetal-ZIFs with varied ratios of Zn/Co, in order to introduce Zn in situ as a structure promoter and Co for an increase of the CO2 conversion. CO2 conversion increased by improving the Co content, while CH4 selectivity also increased obviously. The superior selectivity of value-added hydrocarbons and the ratio of olefins and paraffins (O/P) were obtained without addition of alkali metals. The O/P is 1.76 over FeZnCo-NC-59. The N-doped porous carbon catalysts delivered a good stability in a 1000 h test under harsh reaction conditions. The stable catalysts provide a promising prospect for further application in CO2 hydrogenation.
研究领域:
化学工程
·
催化科学
·
能源转换
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Zejun Zhang,Xiao Han,Lisi Wang,Baoli Wang,Yuhao Huang,Mansoor Ahmad,Zhitan Huang,Amir Badshah,Wei Sun
In this paper, a novel trimetallic zeolitic imidazolate frameworks (ZnCoMn-ZIFs) was successfully synthesized by a facile one-pot method at room temperature, which was further used to prepare a triatomic site anchored in N-doped carbon (Co 2 MnN 8 @C) hybrid nanostructure via a pyrolysis method. The synthesized Co 2 MnN 8 @C was modified on the screen-printed carbon electrode, and the modified electrode was used for the portable wireless sensitive determination of chlorogenic acid (CGA) by differential pulse voltammetry. The Co 2 MnN 8 @C exhibited large surface area and excellent catalytic activity with increasing Co and Mn sites, which could selectively combine with CGA to enhance the sensitivity of the electrochemical sensor. Under the optimized conditions, the constructed sensor had wider linear ranges for CGA analysis from 0.05–10.0 μmol/L and 10.0–100.0 μmol/L with a detection limit of 0.0075 μmol/L (3S 0 /S). The sensor was successfully applied to detect CGA in natural medicine and food samples with satisfied recoveries. Therefore, the proposed strategy may stimulate the exploration of trimetallic ZIFs with more active sites for the development of sensitive electrochemical sensors.
研究领域:
分析化学
·
材料科学
·
药物分析
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Mingjin Xue,Tingzhe Wang,Zewen Wu,Hao Liu,Shunbao Hu,Bingtao Bao,Aihua Tang,Yiting Xu,Weiang Luo,Guorong Chen,Birong Zeng,Conghui Yuan,Lizong Dai
Preparing multifunctional epoxy resin composites with excellent flame retardancy and long-lasting anti-corrosion properties has always been a huge challenge. In this study, we used o -vanillin-based ZIFs to coat multilayered MXene nanosheets in situ to obtain MXene@ZIF nanohybrid materials and subsequently prepared epoxy composites with excellent flame-retardant properties, long-lasting corrosion-resistant properties, and excellent mechanical properties. It was shown that in situ capping with o -vanillin-based ZIFs significantly enhanced the defects of MXene lamellae and improved their dispersion in the matrix. When the MXene@ZIF content was only 3 wt%, the limiting oxygen index (LOI) of EP/MXene@ZIF increased to 28.6 %, and compared with pure EP, its total heat release and total smoke release were reduced by 32.2 % and 16.2 %, respectively. Electrochemical impedance spectroscopy (EIS) and salt spray testing showed that the epoxy composite coating incorporating MXene@ZIF nanosheets had excellent long-term anti-corrosion properties. Even after soaking in 3.5 % NaCl solution for 2400 h, the epoxy composite coating still maintained an impedance value of 1.47 × 10 8 Ω cm 2 . In addition, the mechanical properties of EP/MXene@ZIF were also significantly enhanced. All in all, this study provides a multifunctional modification strategy for epoxy resin via a single filler, expanding the application prospects of epoxy resin composites in different fields.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xiaodong Yang,Feifei Peng,Longfei Zhang,Xiang Wang,Shulin Liu,Wei Yang,Luhong Zhang,Na Yang
Amorphous LDHs materials have been considered promising electrocatalysts for OER since their abundant coordination sites but still undergo poor stability. It is an efficient strategy to rationally architect amorphous/crystalline hybrid nanostructures on the ZIFs-derived amorphous LDH counterparts. Herein, we provide a facile two-step method to fabricate crystalline Ag NPs decorated amorphous QLDHs (Ag/QLDHs) nanosheet arrays on the Ni foam through ions exchange and spontaneous redox reaction. Based on the multi-metal synergetic effects (Co, Zn, Fe, Ni) and regulation of Ag nanoparticles (NPs), the as-formed Ag/QLDHs with heterogeneously hierarchal structures exhibit excellent OER performance with a low overpotential of 216 and 247 mV under 10 and 100 mA cm −2 in 1 M KOH, respectively, together with highly structural robustness. Through using the in situ-Raman spectroscopy, we reveal that the Ag NPs play the important role in enhancing the oxidation state of Ni and Fe species in Ag/QLDHs, which facilitates the generation of active MO x (OH) y at a much lower potential. The synthesized approach proposed in this work will supply a promising pathway for constructing amorphous/crystalline hybrid structures applied to alkaline water oxidation.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Nano Research
·
2023
·
IF 9.9
Fang Diyi,Liu Chuanlei,Chen Yu,Peng Qilong,Wu Kongguo,Chen Yuxiang,Jiang Hao,Wu Yuan,Shen Benxian,Wu Qiumin,Wu Di,Sun Hui
Porous heterogeneous lyophobic systems (HLSs) find potential applications in energy restoring, dissipating, and absorbing. However, the development of controllable HLSs still lacks rational structure design of nanoporous materials matching the molecular sizes of adopted liquids. Besides that, thoroughly understanding the underlying transportation mechanism in the confined nano channels is greatly challenging. In this work, a series of Co/Zn bimetallic zeolitic imidazolate frameworks (ZIFs) with tunable structures were synthesized via regulating the Co to Zn ratios and employed to investigate the intrusion–extrusion of liquid water in confined nanopores. Structural characterizations confirm the heterometallic coordination in the Co/Zn-doped frameworks. Water intrusion–extrusion experiments unlock the relationship between the intrusion pressure and the nanopore size and realize the evolution of the HLSs between molecular spring and shock-absorber. In addition, cycling tests indicate the reversible structure change of Co/Zn ZIFs encountering pressure-induced water intrusion. In combination with molecular dynamics simulations, we present that the water multimers intrude into nanopores of ZIFs in chain-like forms along with dissociation of hydrogen bonds (HBs). Water molecules in the pre-intrusion state exhibit reduced HBs in response to the increase of pressure and linear structure with 1.6–3.0 HBs on average. After transition to the post-intrusion situation, the associative configuration of water tends to exhibit the tetrahedral structure. Herein, we highlight the roles of pore size and HB in synergically dominating the pressure-induced intrusion–extrusion of liquid water in hydrophobic nanopores. Furthermore, the present work can also guide the development of functional guest–host systems based on porous architectures.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Chunjie Li,Xin Qian,Mengyuan Hao,Xuefei Wang,Shiqi Zhu,Mei Guo,Haoting Gong,Yonggang Zhang
PAN-based carbon fibers have been widely used in aerospace materials due to high specific strength , high specific modulus and many other outstanding features. As one kind of carbon-based electromagnetic wave (EMW) absorption material, carbon fibers are expected to absorb more EMW due to multiple polarization losses and large specific surface area in which EMW can be reflected many times. However, they also have certain disadvantages when used as EMW absorption material due to their high dielectric constant, low permeability and low reflection loss strength. Herein, a facile hydrothermal synthesis method was used to construct the three-dimensional (3D) bimetal-organic framework compound onto the surfaces of polyacrylonitrile(PAN)-based ultrahigh modulus carbon fibers (UHMCFs). Through the control of key parameters in the synthesis process, 3D bimetallic ZIF particles with different morphologies were assembled on the fiber surfaces, and a further high temperature heat treatment resulted in significantly improved EMW absorption properties. The results showed that three fibrous structures including rod-shaped, threadlike and flower-like morphologies had been formed with the introduction of CoZn-ZIFs. Among them, the uniform structure of rod-shaped sample could be preserved after carbonization and it also showed optimal EMW absorption performance, e.g. its minimum reflection loss (RL min ) and effective absorption bandwidth (EAB) values were − 67.67 dB (EMW loss above 99.9 %) and 4.28 GHz, respectively, with the thickness of 2.00 mm. In the final, the EMW absorption mechanism of CoZn-bimetallic ZIF decorated UHMCFs including interfacial loss, conductive loss, polarization loss, multiple scattering and excellent impedance matching was discussed in detail.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Le Zhong,Zhongjie Wang,Xiaohong Ye,Jiandong Cui,Ziyuan Wang,Shiru Jia
The catalytic performance of immobilized lipase is greatly influenced by functional support, which attracts growing interest for designing supports to achieve their promotive catalytic activity. Many lipases bind strongly to hydrophobic surfaces where they undergo interfacial activation. Herein, the behavioral differences of lipases with distinct lid structures on interfaces of varying hydrophobicity levels were firstly investigated by molecular simulations. It was found that a reasonable hydrophilic/hydrophobic surface could facilitate the lipase to undergo interfacial activation. Building on these findings, a novel “nest”-like superhydrophobic ZIFs (ZIFN) composed of hydrophobic ligands was prepared for the first time and used to immobilize lipase from Aspergillus oryzae (AOL@ZIFN). The AOL@ZIFN exhibited 2.0-folds higher activity than free lipase in the hydrolysis of p-Nitrophenyl palmitate (p-NPP). Especially, the modification of superhydrophobic ZIFN with an appropriate amount of hydrophilic tannic acid can significantly improve the activity of the immobilized lipase (AOL@ZIFN-TA). The AOL@ZIFN-TA exhibited 30-folds higher activity than free lipase, and still maintained 82% of its initial activity after 5 consecutive cycles, indicating good reusability. These results demonstrated that nanomaterials with rational arrangement of the hydrophilic/hydrophobic surface could facilitate the lipase to undergo interfacial activation and improve its activity, displaying the potential of the extensive application.
研究领域:
生物化学
·
催化
·
材料科学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2023
·
IF 6.1
Yaqi Zhang,Yong Man,Jingna Li,Yaming Sun,Xiuming Jiang,Lijun He,Shusheng Zhang
The aflatoxin B 1 (AFB 1 ) early warning technique based on precursors is an effective strategy for the prevention of AFB 1 contamination risk. The determination of precursors is imperative to ensure the efficiency of the early warning technique. Herein, a controllable magnetic adsorbent Fe 3 O 4 /ZIFs was first introduced for the effective extraction and determination of averantin (AVN) and sterigmatocystin (ST) precursors in cereal by combining magnetic solid-phase extraction (MSPE) and high-performance liquid chromatography (HPLC). Benefiting from the abundant adsorption sites and multifunctional groups matching the analytes , Fe 3 O 4 /ZIFs effectively and simultaneously extracted AVN and ST with great differences in polarity and structure via multiple interactions. AVN was extracted by Fe 3 O 4 /ZIFs mainly through π–π and hydrophobic interactions, while ST was extracted predominantly by electrostatic interactions and surface complexation. The limits of detection were 0.08 μg kg −1 (AVN) and 0.36 μg kg −1 (ST). The developed method exhibited satisfactory spiked recoveries (79.1%–105.4%) in the determination of AVN and ST in rice. This work provides a novel analytical strategy for further studying AFB 1 early warning technique and the formation and transformation of aflatoxins .
研究领域:
分析化学
·
食品安全
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Energy Storage
·
2023
·
IF 9.4
Jing-Zhou Chen,Sheng-Guang Wang,Yun-Lei Hou,Wan-Xin Wen,Hua-Ying Wang,Bo-Han Zhang,Dong-Lin Zhao
The severe volume expansion and low electron mobility of silicon-based anode materials during cycling limit their further practical applications, and the use of a multilayer carbon skeleton network and graphene to encapsulate silicon nanoparticles is an effective strategy to cope with the volume expansion of silicon-alloyed anodes and to improve their electron transport. In this work, a carbon skeleton derived from dual ZIF materials was designed and the controlled growth of carbon nanotubes was achieved by changing the capping order of the ZIF materials, which effectively slowed down the capacity degradation of the battery during the cycling process. At a current density of 1 A g −1 , the specific capacity of Si@D-C-ZIF@CNTs@rGO was maintained at 1498.3 mAh g −1 after 500 cycles, and the capacity was maintained at 96 % after 200 cycles of assembling Si@D-C-ZIF@CNTs@rGO as the anode into a full cell. The design of silicon-based anode materials with multi‑carbon skeletons is given a fresh concept by this work.
研究领域:
材料科学
·
能源存储
·
纳米技术
·
电化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Yucheng Li,Xiangyu Wang,Zhengyin Duan,Dehai Yu,Qiang Wang,Dandan Ji,Wenxia Liu
Treating dye-contaminated wastewater using the visible light–driven photo-Fenton reaction is beneficial to environmental remediation. This paper reports the synthesis of a novel, highly effective photo-Fenton catalyst, the Zn/Co-ZIFs@MIL-101(Fe) composite, by a facile internal-growth method. The composite, which had an MOF-in-MOF structure, activated H 2 O 2 to decompose RhB, a polluting-dye model, under visible-light illumination. The transfer of the electron–hole pair was synergistically accelerated by the reaction centers of the composite (the MIL-101(Fe) shell and Zn/Co-ZIFs core), which enhanced H 2 O 2 activation. The generated OH, O 2 − , and 1 O 2 effectively decomposed RhB. The composite’s catalytic performance was significantly enhanced by the electronic hybridization of its Fe 3+ , Co 2+ , and Zn 2+ metal centers. Thus, the composite demonstrated a remarkable capability to remove RhB. The composite polymetallic MOFs loaded with 3% Zn/Co-ZIFs prepared by us showed good reusability and water stability, and their morphology and structure did not change significantly after four runs, depending on the iron, cobalt, and zinc metal leaching concentrations 0.134 mg/L, 0.06 mg/L and 0.054 mg/L respectively. This study provides a novel method to construct an Zn/Co-ZIFs@MIL-101(Fe) catalyst with dual reaction centers that enhance the transfer of electron–hole pairs. Our findings inspire the application of MOF-based photo-Fenton catalysts to wastewater treatment and environmental remediation.
研究领域:
环境科学
·
催化
·
材料科学
·
水处理
✓ 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）