COMBUSTION AND FLAME
·
2022
·
IF 5.767
Wanjun Zhao,Qingjie Jiao,Pengwan Chen,Shi Yan,Yanli Zhu,Bi Zhang,Xin Zeng,Dazhi Liu,Yapeng Ou,Fang Wang
Zn has been incorporated into Mg via centrifugal atomization in this work. The prepared Mg-Zn alloys have been characterized via SEM/EDS and XRD . The thermal behavior and combustion of Mg-Zn alloys have been tested by TG/DSC and laser ignition. Then, Mg-Zn alloys have been applied in pyrotechnics with PTFE as the oxidizer , followed by measuring the reactivity and ignition delay . Mg-5%Zn and Mg-10%Zn alloys consisting of α-Mg and eutectic phase (α-Mg and MgZn 2 ) in a high degree of sphericity with evenly distributed Zn were obtained. Thermal behavior characterization indicates that the oxidation of Mg-Zn alloys initiates ∼50 °C earlier than Mg along with a higher oxidation rate, which could be attributed to the lower melting point of MgZn 2 and Zn. In addition, the oxidation rate of Mg-Zn alloys is also higher than Mg that is the result of significantly lower apparent activation energy of Mg-Zn alloys than Mg. Due to the great discrepancy of melting and evaporation point between Mg, MgZn 2 , and Zn, a visible microexplosion phenomenon has been observed during the combustion process of Mg-Zn alloys. Then, Mg-Zn alloys have been applied as the fuel to replace Mg in Mg/PTFE pyrotechnics. The ignition delay of Mg-Zn/PTEE composites is shorter than that of Mg/PTFE, which is due to the easier oxidization initiation of Mg-Zn alloys compared to Mg. Besides, the lower melting and evaporation points of MgZn 2 and Zn than Mg can accelerate the combustion of Mg-Zn alloys, leading to the improved peak pressure and reaction rate of Mg-Zn/PTEE. Thus, the lower apparent activation energy of Mg-Zn alloys and the lower melting point of MgZn 2 and Zn could promote the energetic kinetics of Mg-Zn alloys synergistically. Above all, the prepared Mg-Zn alloys in this study are ambitious candidates in pyrotechnics for controllable ignition and reactivity kinetics.
研究领域:
材料科学
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燃烧学
·
烟火技术
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产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2022
·Vol. 51
·期 2
·522-531
·
IF 2.047
Zheng Jie,Chen Jiali,Tang Yu,Shen Kaiyuan,Xiang Yujie,Shen Lanxian,Ge Wen,Yang Peizhi,Deng Shukang
In this study, β -Zn 4 Sb 3 was prepared using the Zn-NaCl mixed-flux method based on the stoichiometric ratio of Zn/Sb/NaCl = (4− x ):3:(7+ x ) ( x = 0, 0.1, 0.2, 0.3). X-ray diffraction results showed that all samples were hexagonal rhombic crystal structures with the space group \(R\overline{3}c\) . A second phase of ZnSb was detected in the samples with x = 0.2 and x = 0.3. In addition, the crystal-cell volume and lattice parameter of all samples increased for the larger ion radius of Na + than Zn 2+ . The transmission electron microscopy image and corresponding area electron diffraction pattern demonstrated that the prepared samples had a complete crystal structure. All samples had hole conduction and exhibited p-type conduction behavior. The carrier concentration of the material increased with increased Na content and decreased Zn, ranging from 8.89 × 10 19 cm −3 to 17.82 × 10 19 cm −3 . Moreover, the thermal conductivity ( κ ) of x = 0–0.2 samples decreased with increased Na content; however, the sample with x = 0.3 had a higher κ owing to the appearance of a ZnSb phase. Thermogravimetric differential thermal analysis showed that no weight loss occurred below the melting point. Eventually, the sample with the nominal composition of β- Zn 3.8 Sb 3 NaCl 7.2 achieved a ZT value of 1.43 at 690 K.
研究领域:
材料科学
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物理学
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2018
·Vol. 20
·期 10
·2212-2217
·
IF 8.586
Mi Feng,Xingmei Lu,Kun Jiang,Jie Zhang,Jiayu Xin,Chunyan Shi,Kefeng Wang,Suojiang Zhang
A one-step method is proposed to prepare a chitin/Zn composite from shrimp shells using urea-Zn(OAc)2·2H2O aqueous solution as a decalcification, deproteinization, and Zn-introduction solvent. The chitin/Zn composite, which contained 34.7 wt% zinc, 1.2 wt% calcium carbonate and 1.6 wt% protein, was obtained under optimal conditions and exhibited an antibacterial effect.
研究领域:
生物材料学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Nan Jiang,Jinlin Zhu,Chang Li,Xi Liu,Xinyu Guo,Chengcheng Zhu,Yan Chen,Yi Zhou,Wenjun Deng,Rui Li
Aqueous zinc-ion batteries (AZIBs) have recently been paid great attention due to their robust safety features, high theoretical capacity, and eco-friendliness, yet their practical application is hindered by the serious dendrite formation and side reactions of Zn metal anode during cycling. Herein, a low-cost small molecule, nicotinamide (NIC), is proposed as an electrolyte additive to effectively regulate the Zn interface, achieving a highly reversible and stable zinc anode without dendrites. NIC molecules not only modify the Zn 2+ solvation structure but also preferentially adsorb on the Zn surface than solvated H 2 O to protect the Zn anode and provide numerous nucleation sites for Zn 2+ to homogenize Zn deposition. Consequently, the addition of 1 wt% NIC enables Zn||Zn symmetric cells an ultra-long lifespan of over 9700 h at 1 mA cm −2 , which expands nearly 808 times compared to that without NIC. The advantages of NIC additives are further demonstrated in NaVO||Zn full cells, which exhibit exceptional capacity retention of 90.3 % after 1000 cycles with a high Coulombic efficiency of 99.9 % at 1 A/g, while the cell operates for only 42 cycles without NIC additive. This strategy presents a promising approach to solving the anode problem, fostering advancements in practical AZIBs.
研究领域:
材料科学
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电化学
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能源存储
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DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Xinhui Liu,Chen Yan,Yilin Wang,Peng Zhang,Siyan Yan,Hanbin Wang,Jianguo Zhuang,Yitao Zhao,Yuchen Wang,Yijun Yu,Qichao Zhao,Xuedong Zhu,Fan Yang
A series of Zn loaded ZSM-5 (Zn/ZSM-5) zeolites were prepared utilizing either Zn(NO 3 ) 2 or Zn-based MOFs (ZIF-61, ZIF-8 and ZIF-14) as Zn sources to explore their effects on the catalysts’ physiochemical properties through characterizations and simulations. Results revealed that hierarchical structures containing meso - to macro- pores of 10 ∼ 80 nm aside from the intrinsic micropores were constructed profiting from the use of Zn-based MOFs. On the other side, lager proportions of medium acid and Lewis acid sites were generated by more Zn(OH) + , whose content was proven to be inextricably linked to the binding energy between Zn and ligand as well as local charge valence state of Zn. Benefitting from hierarchical structures and balanced acidities, Zn/Z5(ZIF-14) employing ZIF-14 as Zn source demonstrated higher aromatic selectivity and longer catalyst lifetime (50.9 % and 26 h) than the microporous counterpart synthesized from zinc nitrate hexahydrate (42.1 % and 20 h) in methanol to aromatics (MTA) reaction.
研究领域:
催化化学
·
材料科学
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DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 14
·146508
·
IF 3.721
Shaolong Li,Yusi Che,Jianxun Song,Yongchun Shu,Jilin He,Baoqiang Xu,Bin Yang
Thermodynamic and kinetic properties of Mg(II) in LiCl-KCl eutectic melt were investigated by electrochemical techniques. The diffusion coefficients of Mg(II) in the melt at various temperatures were studied by cyclic voltammetry, and the activation energy of Mg(II)/Mg was calculated to be (48.5 ± 3.7) kJ mol−1. The exchange current densities and reaction rate constants of Mg(II)/Mg at different temperatures from 773 K to 873 K were calculated by testing polarization curves on Mo electrode, and results showed that the exchange current densities became larger as the temperature increased. Equilibrium potentials of Mg(II)/Mg on Mo electrode and liquid Zn electrode were also tested by open circuit potential method. Subsequently, the apparent standard potential of Mg(II)/Mg, apparent standard Gibbs energy for the formation of MgCl2 and activity coefficients of Mg in the liquid Zn were calculated. Finally, metallic Mg was extracted in the form of Zn-Mg alloys by galvanostatic electrolysis on liquid Zn electrode. The deposit was analyzed by X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, and Mg2Zn11 was detected in the deposit.
研究领域:
冶金学
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电化学
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产品关联
DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 12
·1383
·
IF 2.935
Jian Shen,Nan Wang,Yang Guang Wang,Di Yu,Xiao–kun Ouyang
Composite adsorption materials combine the advantages of various adsorptive materials and compensate for the defects of single adsorbents. Magnetic montmorillonite (MMMT) shows good adsorption properties for Pb(II). In order to further improve the adsorption properties of MMMT, in this work, Zn-BDC, a kind of metal–organic framework (MOF), was modified onto the surface of MMMT by in situ polymerization. The composite material MMMT@Zn-BDC was characterized by Zetasizer, SEM, TEM, FTIR, XRD, VSM, and XPS. The influence of adsorption conditions on the adsorption capacity of MMMT@Zn-BDC for Pb(II) was examined, including the adsorbent dosage, pH of Pb(II) solution, initial concentration of Pb(II), and the temperature and adsorption time. Also, the adsorption mechanism was studied. The results of this study show that MMMT@Zn-BDC adsorbs Pb(II) via chemisorption. In addition, MMMT@Zn-BDC exhibits good potential for adsorbing Pb(II), including its high adsorption capacity (724.64 mg/g) and good recyclability.Keywords:Zn-BDC;magnetic montmorillonite;Pb(II);adsorption
研究领域:
材料科学
·
环境科学
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产品关联
DOI
PubMed
高影响因子
AMERICAN MINERALOGIST
·
2023
·Vol. 108
·期 7
·1357-1367
·
IF 3.1
Qi Tao,Chaogang Xing,Seungyeol Lee,Long Yang,Qingjin Zeng,Shangying Li,Tianqi Zhang,Guanglie Lv,Hongping He,Sridhar Komarneni
An aluminum-free zinc-bearing smectite (Zn-smectite) was synthesized under hydrothermal conditions, together with its magnesium substituted products. Its layer charge calculated by cation exchange capacity (CEC) is 117.4 mmol/100 g. Powder X-ray diffraction (XRD) revealed turbostratic stacking and showed that the d 06l value of the Zn-smectite was >1.525 Å, indicating that it is trioctahedral. Its d 001 value increased from ca.12.8 Å to ca. 16.0 Å after ethylene glycol (EG) saturation. The Zn-smectite did not irreversibly collapse after heating the Li + -saturated sample to 300 °C, suggesting that its layer charge was generated from octahedral-site vacancies (defects). The Zn-smectite resembles zincsilitelike minerals with interlayer Na + and Zn 2+ . The intralayer structure of zincsilite was confirmed by pair distribution function (PDF) analysis, and the whole crystal structure was built and optimized by DFT calculation in the CASTEP module of the Materials Studio software. Synthetic zincsilite is triclinic, space group P 1, and its optimized unit-cell parameters are: a = 5.294 Å, b = 9.162 Å, c = 12.800 Å, α = 90.788°, β = 98.345°, and γ = 90.399°.
研究领域:
矿物学
·
材料科学
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DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 7
·719
·
IF 4.501
Hong-Juan Qin,Yu-Hang Zhang,Zhen Wang,Gui-Hua Yang
Photocatalysis provides a prospective approach for achieving high-value products under mild conditions. To realize this, constructing a selective, low-cost and environmentally friendly photocatalyst is the most critical factor. In this study, BiOBr/Zn@SnO2is fabricated by a one-pot hydrothermal synthesis method and BiOBr: SnO2ratio is 3:1; this material is applied as photocatalyst in fructose selective conversion to lactic acid. The bandgap structure can be regulated via two-step modification, which includes Zn doping SnO2and Zn@SnO2coupling BiOBr. The photocatalyst shows excellent conversion efficiency in fructose and high selectivity in lactic acid generation under alkaline conditions. The conversion rate is almost 100%, and the lactic acid yield is 79.6% under optimal reaction conditions. The catalyst is highly sustainable in reusability; the lactic acid yield can reach 67.4% after five runs. The possible reaction mechanism is also proposed to disclose the photocatalysis processes.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
BIOMASS & BIOENERGY
·
2025
·
IF 5.8
Zhaojie Qin,Dongmei Bi,Bozheng Li,Xiang Zhu,Yu Ni,Lihong Wang
Furfural (FF) is a platform chemical with high value and wide application. The catalysts (Zinc oxide modified magnesium-aluminum spinel catalyst (Zn/MgAl 2 O 4 )) prepared in this paper allowed for the fast and efficient preparation of FF. Catalytic pyrolysis experiments were carried out on three typical biomass, and it was found that Zn/MgAl 2 O 4 had a significant enrichment effect on the production of FF in bio-oil. And the effect was more pronounced in the camphor wood experiments. Under pyrolysis conditions (400 °C, catalyst to biomass mass ratio is 1:1), FF relative content reached 64.31 wt%. Zn 2+ increased the acidic sites in Zn/MgAl 2 O 4 and accelerates proton transfer. Glycosidic bond cleavage and monomer degradation were significantly enhanced, resulting in improved FF conversion efficiency. The relative content of FF in the bio-oils obtained from pyrolysis of the three biomass feedstock in the temperature range of 400–600 °C was more than 50 wt%, and the results were better at low temperatures. The results of this paper can provide a theoretical basis for the preparation of FF from clean energy biomass.
研究领域:
能源生物学
·
催化化学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS RESEARCH
·
2017
·Vol. 32
·期 18
·3585-3592
·
IF 1.673
Xinjun Shi,Jinju Zheng,Minhui Shang,Tingting Xie,Jiangbo Xie,Sheng Cao,Weiyou Yang
In this work, we reported the growth of cadmium-free Ag-doped Zn–In–S nanocrystals (NCs) with effective photoluminescence (PL) via a hot-injection strategy. The effects of the nucleation temperatures, reaction times, and Ag-doping concentrations on the PL properties of Ag-doped Zn–In–S NCs were investigated systematically. The as-synthesized NCs exhibit color-tunable PL emissions covering a broad visible range of 472–585 nm. After being passivated by a protective ZnS shell, the PL quantum yield (QY) of the resultant NCs was greatly improved up to 33%. With the increase of the Ag-doping level, the PL is significantly intensified due to the improved concentration of Ag ions which provides more holes to recombine with electrons from the bottom of the conduction band. This also makes the emission via the dopant energy level become a powerful, competitive advantage for the NCs with higher Ag-doping levels, resulting in a longer lifetime and higher PL QY. These results suggest that tailoring the Ag-doping level can be a powerful strategy to control the optical properties of Ag-doped Zn–In–S NCs.
研究领域:
材料科学
·
光学
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产品关联
DOI
高影响因子
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
·
2017
·Vol. 90
·期 10
·1152-1156
·
IF 2.297
Li Yuanyuan,Su Yuqun,Xu Jing,Xu Zhen-liang,Xu Haitao
In this study, a new Zn coordination polymer (Zn-CP), hereafter, 1Zn, was successfully assembled in a solvothermal system, exhibiting one-dimensional extended chains. 1Zn morphologies were controlled by temperature and surfactants. In addition, the catalytic performance of 1Zn microsized CP was investigated. Knoevenagel condensation after 4 h afforded a conversion of 86%, and a conversion greater than 96% was obtained for 4-chlorobenzaldehyde and 4-bromobenzaldehyde because of their electron-withdrawing ligands. In addition, excellent selectivity was achieved for the degradation (64% conversion) of malachite green in aqueous solution. The microcrystal morphology affected the conversion, and a relative catalytic mechanism was proposed. The developed strategy of shape-controlled assembled CPs will certainly enhance new potential applications of micro-CPs.
研究领域:
材料科学
·
化学
·
催化
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DOI
高影响因子
危险品化学品经营许可证（带存储）