CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Lei Cai,Fei Pan,Xiaojie Zhu,Yanyan Dong,Yuyang Shi,Zhen Xiang,Jie Cheng,Haojie Jiang,Zhong Shi,Wei Lu
Exploring high-performance microwave absorbing materials with lightweight, thin thickness and strong electromagnetic wave (EMW) absorption capability is an essential way to solve EMW pollution problems. Herein, layered N-doped MXene (Ti 3 CNT x ) flakes and hollow Co-ZIF particles (HCF) hybrids were successfully fabricated using the controllable cooperative protection etching strategy and the electrostatic self-assembly technology . Remarkably, the microwave absorption hybrids achieved ultrathin (1.43 mm), and strong EMW absorption ability (reflection loss of −55.02 dB) with a rather low filler loading, which is superior to the magnetic–dielectric hybrids with similar components reported in the literatures. The synergistic effect generated by the improvement of dielectric loss , magnetic loss and interface polarization could effectively integrate with the impedance matching to improve the attenuation ability of EMW. Therefore, this simple assembly and etching strategy opens a new platform for designing hollow and layered materials and broadens the desirable candidates for lightweight and high-efficient microwave absorbers.
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高影响因子
ENVIRONMENTAL RESEARCH
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2021
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IF 6.498
Rui Luo,Junwen Wu,Jing Zhao,Dong Fang,Zongtang Liu,Lin Hu
The non-radical oxidation processes of persulfate activation by carbon materials have shown great potential for industrial and saline wastewater treatment . Recently, metal-organic frameworks (MOFs) as an emerging precursor have been widely used for fabricating functional carbon materials. Herein, we reported ZIF-8 derived defect-rich nitrogen-doped carbon (ZCNs) via NaCl-assisted pyrolysis for efficient non-radical activation of peroxydisulfate to degrade rhodamine B (RB). All samples exhibited excellent catalytic activity , and ZCN-900 (pyrolyzed at 900 °C) was found to be the most active, able to degrade 96 % of RB quickly within 10 min. Quenching tests and electron paramagnetic resonance (EPR) analyses suggested that the singlet oxygen ( 1 O 2 ) dominated the degradation process by a non-radical pathway. Furthermore, the effect of anions and water quality on RB oxidation were investigated, and ZCN-900/PDS system showed great resistance to the anions and natural organic matters (NOM). This work may provide a significant addition to MOF-based functional materials for environmental remediation based on the results above.
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
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IF 5.316
Cheng Cheng,Jian Wang,Zhihao Zhao,Changchun Chen,Sheng Cui,Yifeng Wang,Lin Pan,Yaru Ni,Chunhua Lu
Semiconductor catalyst with high photocatalytic activity can be exploited via heterojunction. In this study, a new S-scheme SrTiO 3 /porous ZnO composite was rationally devised, successfully prepared by utilizing a two-step pyrolysis of SrTiO 3 /ZIF-8, and analyzed by various characterization technologies including XRD, SEM, TEM, BET, XPS, PL, UV–vis DRS, and photoelectrochemical and DFT theoretical calculations. A porous structure, tight contact, and a heterojunction formed between SrTiO 3 and porous ZnO (ZnOT) can be observed by SEM and TEM images. BET testing indicates that the SrTiO 3 /porous ZnO composite (S3ZT) shows the highest specific surface area (30.37 m 2 /g). The band gap values (E g ) of SrTiO 3 and ZnOT are around 3.17 and 2.95 eV, which agree with those obtained from DFT calculations. Compared to other samples, the SrTiO 3 /porous ZnO composite (S3ZT) shows higher light absorption and lower transfer resistance as demonstrated by UV–vis DRS and EIS results. S3ZT presents a superior photocatalytic efficiency of 48.8% in degrading 5 mg/L methyl orange (MO) irradiated by 1 h UV–vis light, which are 7- and 1.5-fold higher than pristine SrTiO 3 and ZnOT, respectively. Moreover, based on Mott-Schottky theory, active species trapping experiments, XPS determination, and DFT calculations (energy band gap and work function), it was shown to be reasonable to utilize the S-scheme charge migration process for an explanation regarding the better photocatalytic activity of SrTiO 3 /porous ZnO composite. Overall, this work will provide an effective protocol for devising and preparing semiconductor photocatalysts with S-scheme heterojunction by utilizing the superior characteristics of MOFs.
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APPLIED SURFACE SCIENCE
·
2021
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IF 6.707
Jinchang Xu,Guofeng Liang,Di Chen,Zilong Li,Hao Zhang,Jian Chen,Fangyan Xie,Yanshuo Jin,Nan Wang,Hui Meng
H 2 -O 2 proton exchange membrane fuel cells (PEMFCs), one of the applications of hydrogen energy with specific energy density of 143 MJ/kg, might be a promising alternative to replace the use of fossil energy. The key to accelerate the application of PEMFCs is to design an efficient non-precious metal catalyst to lower the overpotential of the cathode oxygen reduction reaction (ORR). Herein, we developed a novel iron and nitrogen doped carbon (FeNC) catalyst using ferrocene as iron source, ZIF-8 as organic framework as well as the main carbon source. The regular morphology of ZIF-8 and ferrocene can prevent active sites from agglomeration, resulting a homogenous distribution of Fe, N and C. Moreover, the high specific area, porous structure and abundant catalytic Fe and N species gave rise to the ORR performance of the catalyst. As a result, the as-prepared FeNC catalyst showed an onset and half-wave potential of 0.95 V and 0.78 V in 0.1 M HClO 4 with 1600 rpm, respectively. The catalysts were also applied in a PEMFC as the cathode catalysts with an open circuit voltage of more than 0.9 V and a maximum power density of 601 mW/cm 2 . Additionally, the as-prepared FeNC-1:30 catalyst showed a current density of 380 mA/cm 2 at 0.7 V, which outperformed other as-prepared catalysts.
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Catalysis Science & Technology
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2021
·Vol. 12
·期 4
·1144-1158
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IF 6.119
Junke Li,Mei Li,Zhiliang Jin
An S-scheme surface heterojunction between Co3S4 and Mo2S3 was constructed successfully via a stepwise hydrothermal method. A rhombic dodecahedral cobalt-based metal–organic zeolite imidazole framework (ZIF-67) is used as the cobalt source and template to participate in the reaction process. ZIF-67 with a dodecahedral structure is first reshaped into cobalt sulfide with a hollow polyhedral structure via a one-step sulfidation reaction. And then, Mo and S species were introduced on the surface of Co3S4 to fabricate Co3S4@Mo2S3 with a hierarchical core–shell structure and S-scheme heterojunction. In comparison, the H2 evolution activity of Co3S4@Mo2S3 is about 7 and 3 times higher than those of pure Mo2S3 and Co3S4. Density functional theory (DFT) calculations were used to construct the molecular model of Co3S4 and Mo2S3, and the sample's energy band structure was also analyzed. Based on the analysis of a series of characterization results, a H2 evolution mechanism of Co3S4@Mo2S3 with a S-scheme surface heterojunction was proposed. The formation of the S-scheme surface heterojunction between Co3S4 and Mo2S3 results in a more developed channel to transfer photogenerated electrons and allows the system to retain a more effective redox potential. Besides, the Mo2S3 nanosheet's criss-cross growth on the Co3S4 surface is beneficial to the improvement of the cycle stability of the Co3S4@Mo2S3 composite. This work uses a ZIF-67 polyhedron as the template to provide a new strategy for preparing a hierarchical S-scheme surface heterojunction photocatalyst based on MOFs.
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Nanomaterials
·
2021
·Vol. 11
·期 9
·2171
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IF 5.076
Le Wang,Pengxue Sun,Yiyu Yang,Hanzhen Qiao,Hailong Tian,Dapeng Wu,Shuoye Yang,Qipeng Yuan,Jinshui Wang
The field of enzyme cascades in limited microscale or nanoscale environments has undergone a quick growth and attracted increasing interests in the field of rapid development of systems chemistry. In this study, alcohol dehydrogenase (ADH), lactate dehydrogenase (LDH), and mesoporous silica nanoparticles (MSN) immobilized nicotinamide adenine dinucleotide (NAD+) were successfully immobilized on the zeolitic imidazolate frameworks (ZIFs). This immobilized product was named ZIF@ADH/NAD-MSN/LDH, and the effect of the multi-enzyme cascade was studied by measuring the catalytic synthesis of lactic acid. The loading efficiency of the enzyme in the in-situ co-immobilization method reached 92.65%. The synthesis rate of lactic acid was increased to 70.10%, which was about 2.82 times that of the free enzyme under the optimal conditions (40 °C, pH = 8). Additionally, ZIF@ADH/NAD-MSN/LDH had experimental stability (71.67% relative activity after four experiments) and storage stability (93.45% relative activity after three weeks of storage at 4 °C; 76.89% relative activity after incubation in acetonitrile-aqueous solution for 1 h; 27.42% relative activity after incubation in 15% N, N-Dimethylformamide (DMF) solution for 1 h). In summary, in this paper, the cyclic regeneration of coenzymes was achieved, and the reaction efficiency of the multi-enzyme biocatalytic cascade was improved due to the reduction of substrate diffusion.Keywords:confinement effect;multi-enzyme catalytic cascade;in-situ synthesis;coenzyme recycling;co-immobilization enzyme
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JOURNAL OF MEMBRANE SCIENCE
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2021
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IF 8.742
Zenghui Mai,Senqing Fan,Yilin Wang,Jiaojiao Chen,Yu Chen,Ke Bai,Lei Deng,Zeyi Xiao
An Ag@PAN catalytic nanofiber composite membrane has been fabricated by combining electrospinning PAN nanofiber seeding with 2-MI and flowing synthesis. ZIF-8 can be immobilized on the surface of the nanofibers with Zn(NO 3 ) 2 solution flowing through the 2-MI/PAN nanofiber membrane and Ag nanoparticles can be immobilized on the nanofibers with Zn 2+ in ZIF-8 exchanged by Ag + followed with reduction reaction. The characteristics of XRD , XPS , FTIR, TGA, HRTEM , and BET proved the successful immobilization of Ag nanoparticles derived from ZIF-8 on PAN nanofiber. The permeance of the Ag@PAN catalytic nanofiber composite membrane can reach 19,227 L m −2 h −1 bar −1 with Ag nanoparticles immobilization amount of 49.64%. The p -NP conversion reaction is addressed for the catalytic performance of the Ag@PAN catalytic nanofiber composite membrane. The conversion rate of 99% can be achieved under the condition of p -NP concentration of 0.025 mM and membrane flux of 300 L m −2 h −1 . The apparent reaction rate constant of 236.63 min −1 can be achieved by flowing through mode, which is 4-5 orders of magnitude higher than that in a stirred tank reactor with Ag powders as the catalyst. The catalytic performance of the composite membranes has not declined significantly after ten cycles of the catalysis experiment, implied the good repeatability of the Ag@PAN catalytic nanofiber composite membranes.
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高影响因子
MICROCHIMICA ACTA
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2021
·Vol. 188
·期 11
·1-10
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IF 5.833
Zhou Shiying,Wang Xianfeng,Zhao Peng,Zheng Jilin,Yang Mei,Huo Danqun,Hou Changjun
ZIF-67-derived Co nanoparticles supported on N-doped carbon skeletons have been prepared from melamine foam (Co-NPs/NCs) for non-enzymatic electrochemical H 2 O 2 detection. The synthesis of Co-NPs/NCs was demonstrated via calcination treatment using melamine foam (MF) and ZIF-67 as precursors. The experimental results show that Co-NPs/NCs composites exhibit eminent catalytic activity toward specific determination of H 2 O 2 with high selectivity and sensitivity (252.43 and 203.88 μA mM −1 cm −2 ), low LOD (0.12 μM), and wide linear ranges (10–2080 and 2080–11,800 μM). The excellent performance might be ascribed to the synergetic effects of MOF and N-doped carbon skeletons. The carbon skeletons serve as a conductive bridge and provide a large specific surface area, which can facilitate electron transfer and well disperse nanoparticles. This non-enzymatic electrochemical sensor based on Co-NPs/NCs can successfully detect H 2 O 2 secreted by living cells, indicating its great potential in the early diagnosis and pathological exploration of disease. Graphical abstract
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高影响因子
Polymers
·
2021
·Vol. 13
·期 16
·2646
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IF 4.329
Kunpeng Song,Yinjie Wang,Fang Ruan,Weiwei Yang,Zhuqing Fang,Dongsen Zheng,Xueli Li,Nianhua Li,Meizhuang Qiao,Jiping Liu
Developing superior properties of epoxy resin composites with high fire resistance, light smoke, and low toxicity has been the focus of the research in the flame-retardant field. In particular, it is essential to decrease the emissions of toxic gases and smoke particles generated during the thermal decomposition of epoxy resin (EP) to satisfy the industrial requirements for environmental protection and safety. Consequently, the PZS@ZIF-67 composite was designed and synthesized by employing the hydroxyl group-containing polyphosphazene (poly(cyclotriphosphazene-co-4,4′-dihydroxydiphenylsulfone), PZS) as both the interfacial compatibility and an in situ template and the ZIF-67 nanocrystal as a nanoscale coating and flame-retardant cooperative. ZIF-67 nanocrystal with multidimensional nanostructures was uniformly wrapped on the surface of PZS microspheres. Subsequently, the acquired PZS@ZIF-67 composite was incorporated into the epoxy resin to prepare composite samples for the study of their fire safety, toxicity suppression, and mechanical performance. Herein, the EP/5% PZS@ZIF-67 passed the V-0 rating in a UL-94 test with a 31.9% limit oxygen index value. More precisely, it is endowed with a decline of 51.08%, 28.26%, and 37.87% of the peak heat release rate, the total heat release, and the total smoke production, respectively. In addition, the unique structure of PZS@ZIF-67 microsphere presented a slight impact on the mechanical properties of EP composites at low loading. The PZS@ZIF-67 possible flame-retardant mechanism was speculated based on the analysis of the condensed phase and the gas phase of EP composites.Keywords:flame retardant;polyphosphazenes;ZIF-67;epoxy resin;mechanism of flame retardant
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JOURNAL OF HAZARDOUS MATERIALS
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2021
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IF 10.588
Yeqiang Lu,Shiyang Li,Fuyou Chen,Hui Ma,Congjie Gao,Lixin Xue
Development of efficient absorbent materials for oil spillage clean-up and environmental pollution remediation is highly desired but remains a challenge. In this work, superhydrophobic/superoleophilic polysulfone based ZIF-7 composite (SPZ) foams were fabricated via chemical modification of polysulfone and integrating with hydrophobic coin-shaped ZIF-7 particles. The synergistic approaches provided the SPZ foams with high porosity, low density and superhydrophobic/superoleophilic features ( θ water =162.3°, θ oil =0°) and outstanding self-cleaning property. The as-prepared SPZ foams exhibited highly selective absorption capacity (up to 3800 wt%) for various kinds of oils and organic solvents. Furthermore, the SPZ foams still maintained 95.2% of its pristine absorption capacity and the θ water remained at 143.6° after ten absorption/distillation cycles. The SPZ foam showed outstanding separation ability towards different types of emulsions with separation efficiency all above 97%. The high oil/water separation efficiency and robust reusability made the SPZ foams promising absorbent in dealing with practical oil spills.
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高影响因子
Analytical Methods
·
2021
·Vol. 13
·期 20
·2338-2344
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IF 2.896
Hexiang Li,Fawei Zhu,Jun Xiang,Fangbin Wang,Qi Liu,Xiaoqing Chen
We herein report a facile and scalable strategy for the fabrication of a metal–organic framework (MOF) based composite by in situ growing ZIF-8 on gold nanoparticle (AuNP) loaded magnetic carbon nanotubes (mCNTs). AuNPs were firstly loaded on PEI (polyethylenimine) modified mCNTs by electrostatic forces, and then AuNPs/mCNTs were encapsulated into the ZIF-8 frame through in situ self-assembling of zinc ions and 2-methylimidazole. The morphology, spectroscopy and structural properties of the AuNP/mCNT@ZIF-8 nanocomposites were systematically characterized. The conductivity–strain tests revealed that the in situ insertion of AuNPs/mCNTs in ZIF-8 could not only shorten the electron transfer distance between active sites and mCNTs, but also increase the dispersion of mCNTs, which would benefit the electron and mass transfer. Besides, by adopting the AuNP/mCNT@ZIF-8 nanocomposite-modified glassy carbon electrode (GCE) as the working electrode, a novel electrochemical sensor was successfully developed for the detection of bisphenol A (BPA). A linear range of BPA detection from 1 μM to 100 μM with a limit of detection of 690 nM was favorably obtained. Moreover, the developed sensor exhibited satisfactory reproducibility and superior stability with excellent anti-interference ability, and was successfully applied in the detection of BPA in real samples.
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
·
IF 8.742
Qiuchen Wang,Yan Dai,Xuehua Ruan,Wenji Zheng,Xiaoming Yan,Xiangcun Li,Gaohong He
Carbon nanotubes (CNTs) with 1D gas transport channel has great prospect in MMMs based CO 2 separation. However, the insufficient compatibility with polymer and inner diameter of CNTs limit further improvement of their CO 2 separation performances. In this work, the unique ZIF-8 hollow nanotubes (HNTs) were proposed to construct high-speed gas transmission channel in MMMs by a three-step method (electrospinning-calcination-hydrothermal), aiming at concurrently improving the gas permeability and selectivity. The hollow inner cavity provides long-range and low-resistance gas transmission channels to ensure high gas permeability. At the same time, the ZIF-8 crystals composing the tube wall can not only screen for gas molecules pair, but also strengthen the affinity between the filler and polymer matrix by its organic ligands, thus the gas selectivity can be raised. Compared with ZIF-8 nanoparticles and ZnO HNTs, ZIF-8 HNTs based MMMs present competitive CO 2 separation. When the loading of ZIF-8 HNTs is 5 wt%, the gas separation performance shows the best, in which the CO 2 permeability is 147 Barrer and the CO 2 /N 2 selectivity is 68, approaching to the 2008 Robeson upper limit and surpassing most reported CNTs/Pebax based membranes. Therefore, the proposed ZIF-8 HNTs are promising for MMMs based CO 2 separation.
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