SENSORS AND ACTUATORS B-CHEMICAL
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2018
·
IF 5.667
Zheng Shen,Xindong Zhang,Xiaohui Ma,Ruoning Mi,Yu Chen,Shengping Ruan
A novel hierarchical ZnO rose-like architecture assembled by porous nanosheets was synthesized through a facile hydrothermal method combined with calcination process and used to fabricate gas sensors. The gas sensing measurements showed that the samples exhibited superior individual BTX (benzene, toluene and xylene) sensing properties. By designing more tiny pores on hierarchical rose petal-like nanosheet surface, the specific surface area of the samples was further extended. Besides, highly dispersed Au nanoparticles were grown on the ZnO rose-like architectures to enhance the gas sensing performance via a precipitation manner. Transmission electron microscopy (TEM) analyses indicated the average grain size of these Au nanoparticles was about 3 nm. The gas sensing results showed that the responses of the Au-ZnO sensor to 20 ppm individual benzene, toluene and xylene were 16.25 46.43 and 76.47, which were 4.33, 4.47 and 6.51 times higher than those of the pure specimens. Besides, the optimal working temperature was also decreased from 302 °C to 206 °C. The Au-ZnO sensor also exhibited short response/recovery times, low-concentration detection capability and good stability. The schottky contact between Au and ZnO, catalytic activity of Au nanoparticles and the specific ZnO porous rose-like architectures could be three pivotal factors for the superior BTX sensing properties.
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
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Jiadong Wang,Min Wang,Xi Zhang,Yang Han,Yingxue Wu,Dong Wang,Xuan Qin,Yonglai Lu,Liqun Zhang
Polyurethane (PU) with microphase separation has garnered significant attention due to its highly designable molecular structure and a wide range of adjustable properties. However, there is currently a lack of systematic approaches for quantifying PU’s microphase separation. To address this research gap, we utilized an atomic force microscopy (AFM) nanomechanical mapping technique along with Gaussian fitting to recolor and quantitatively analyze the evolution of PU’s microphase separation. By varying the ratios of the chain extender to cross-linking agent, we observed the changes in the hydrogen bonding between the soft and hard segments. As the ratio of the chain extender to cross-linking agent decreases, the strength of the hydrogen bonding weakens, resulting in a reduction in the quantity and phase percentage of hard segment (HS) domains. Consequently, the degree of microphase separation between the soft and hard segments decreases, leading to specific alterations in the material’s mechanical properties and dynamic viscoelasticity. To further investigate the hierarchical structure of PU, we employed various techniques, such as X-ray analysis, transmission electron microscopy (TEM), and AFM-based infrared spectroscopy (AFM-IR). Our findings reveal a spherulite pattern composed of lamellae within the HS domains, with the cross-linking density gradually increasing from the center to the periphery. Overall, our comprehensive characterization of PU provides valuable insights into its hierarchical structure and establishes a quantitative framework to explore the intricate relationship between the structure and properties.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2014
·Vol. 16
·期 38
·9054-9062
·
IF 3.858
Zongjian Liu,Yuanyuan Chen,Yifan Zheng
We propose a novel strategy for the synthesis of materials with a hierarchical structure. This strategy is based on in situ combination of two processes, namely, capping agent-mediated oriented growth and stirring-induced aggregation, and the growth of Cu crystals in the presence of linear alkyl diamines of short carbon chain length under vigorous stirring is shown to demonstrate its feasibility. Our experimental results have shown that the oriented growth of Cu nanowires can be significantly disturbed by vigorous stirring, resulting in large-scale growth of hierarchical dendritic Cu crystals. The morphology of grown dendritic Cu crystals has been found to vary with the stirring rate, type of diamine, and diamine concentration, which makes it possible to prepare hierarchical Cu structures of various morphologies. The growth mechanism of these hierarchical Cu structures is proposed based on the experimental observations. The present unique strategy offers a fresh way to fabricate materials with a hierarchical structure.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Qinglei Sun,Mei Tang,Peter Vang Hendriksen,Bo Chen
A novel hierarchically porous magnetic ZnFe 2 O 4 /MgAl-layered double hydroxide (LDH) was reported as an effective adsorbent for the elimination of Congo Red (CR) from water. Three-dimensional stackable MgAl-LDH nanosheets synthesized through hydrothermal method were attached to the surface of ZnFe 2 O 4 microsphere , using the inexpensive, non-toxic, quick and simple bio-template technique. Mg/Al molar ratios played a crucial role in crystal phase synthesis and adsorption capacity. Adsorption kinetics and thermodynamics of CR adsorption by ZnFe 2 O 4 /MgAl-LDH were also investigated. The adsorption kinetics followed the pseudo-second-order. The maximum adsorption capacity (294.12 mg g −1 ) was obtained by the ZnFe 2 O 4 /MgAl-LDH with Mg/Al molar of 2, which was more productive than the base adsorbent without MgAl-LDH attaching (28.58 mg g −1 ). Adsorption isotherm revealed Langmuir-type monolayer adsorption. The adsorption processes were spontaneous and endothermic in nature. Absorbents fabricated in this work could be easily regenerated by rinsing the material in methanol and magnetically separated from the solution. Adsorbent synthesized in this work is very promising composite for purification of water from toxic chemicals.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Yan Wang,Xiaochuang Di,Zhao Lu,Xinming Wu
Nowadays, electromagnetic (EM) radiation poses severe environmental pollution and harm to civilian and military life. To this end, it is urgent to synthesize high-efficiency microwave absorbers in terms of composition and structural design. Herein, we reported a unique hybrid nanostructure with Co particles embedded in hollow carbon polyhedron by a series of synthetic steps including carbonization and pyrolysis . Further, the nanoporous carbon (NPC) derived from wheat flour is coated onto the surface of Co@C polyhedrons, forming a special hierarchical structure (Co@C@NPC), which demonstrates outstanding microwave absorption properties due to the hierarchical porous structure, enhanced interfacial polarization, conduction loss, multi-reflection and matched impedance. Typically, with a 10 wt% filler content, the maximum R L of Co@C@NPC reaches −57.2 dB at 9.6 GHz and the corresponding effective bandwidth is 5.7 GHz (from 7.5 to 13.2 GHz) with an absorber thickness of 3 mm. Besides, the filler loading of 10 wt% is much lower than other reported bio-derived absorbers. In short, the hybrid zeolitic imidazolate frameworks offer a novel idea for constructing hollow carbon skeletons and introducing biomass carbon as a green, low cost and renewable material that enhances the dielectric loss and the synergistic effect between permittivity and permeability.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2016
·
IF 2.848
Jia-liang Lv,Qing-da An,Wei Zheng,Yuan Fan,Zhi-min Lei,Shang-ru Zhai
There is an interesting yet challenging task to develop a facile procedure for designing multifunctional carbonaceous materials for environmental applications. In this research, multifunctional hierarchical cabbage-like carbonaceous materials (Fe/CCMs-X) have been fabricated via a facile hydrothermal carbonization (HTC) of furfural in the presence of cobalt acetylacetonate, followed by simple impregnation iron salts and heating treatment. The structure, morphology and magnetic properties were characterized by powder X-ray diffraction (XRD), N 2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM) techniques; and its adsorption behaviors of Cr(VI) were investigated in detail. Batch experiments were conducted at relatively mild conditions (pH ∼ 3). The adsorption equilibrium data was best fitted by Langmuir isotherm model and the adsorption kinetics followed pseudo-second-order models. The maximum capacity predicted by the Langmuir model is 75.3 mg/g for Fe/CCMs-800. Furthermore, thermodynamic parameters (Δ H > 0, Δ S > 0, and Δ G < 0) revealed that the sorption reaction was a spontaneous and endothermic process. Most of important, the excellent magnetism (79.9 emu g −1 ) provided an ideal magnetic-separation performance from aqueous systems. It demonstrated that this newly prepared multifunctional hierarchical carbonaceous materials (Fe/CCMs-X) are promising sorbents for chromium(VI) ions removal from water.
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
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Yuantao Li,Jiajun Zhu,Jiyang Xie,Yongyun Mao,Wanbiao Hu
Constructing three-dimensional (3D) hierarchical bimetallic pseudocapacitive materials with abundant opening channel and heterojunction structures is rather promising but still challenging for high-performance supercapacitors. Herein, a self-sacrifice-template epitaxial growth strategy was proposed for the first time to construct 3D hierarchical bimetallic pseudocapacitive material. By using this strategy, NiCo 2 O 4 nanowires (NiCo 2 O 4 NW) arrayed randomly to form a porous shell via in-situ epitaxial growth fully enclosing a MnO 2 tube core, forming multiple transport channels and nano-heterojunctions between MnO 2 and NiCo 2 O 4 NW, which facilitates electron transfer, i.e. exhibiting high electronic conductivity than any single component. As a result of the self-sacrifice-template epitaxial growth method, special hollow tectorum-like 3D hierarchical structure with considerable inter-nanowire space and hollow interior space enables easy access of electrolyte to NiCo 2 O 4 NW surface and MnO 2 core, thereby resulting in highly exposed redox active sites of MnO 2 core and NiCo 2 O 4 NW shell for energy storage. Comprehensive evaluations confirmed MnO 2 @NiCo 2 O 4 NW was a supercapacitor electrode candidate, delivering a superior energy density of 106.37 Wh kg −1 . Such performance can be ascribed to the synergistic coupling effect of 3D hierarchical tube and nano-heterojunction structures. The proposed self-sacrifice-template epitaxial growth strategy provides important guidance for designing high-performance energy storage materials.
研究领域:
材料科学
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储能技术
·
纳米材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS RESEARCH BULLETIN
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2019
·
IF 3.355
Long-Cheng Zhang,Min-Qiang Wang,Hao Chen,Heng Liu,Ying Wang,Long-Zhen Zhang,Guo-Rong Hou,Shu-Juan Bao
Large-scale electrochemical water splitting is hindered by the sluggish oxygen evolution reaction (OER) kinetics. In this work, we report a vertically standing Fe 3 O 4 -FeSe/CoSe 2 hierarchical structure material grown on carbon cloth as a highly active OER electrocatalyst . Benefiting from the rock-like Fe 3 O 4 particles on the carbon cloth, the CoSe 2 nano-arrays are more firmly affixed onto the carbon cloth. In addition, small amount of FeSe particles adsorbed on the CoSe 2 arrays offer a synergistic advantage, in which CoSe 2 achieved a small 279 mV overpotential at a current density of 10 mA cm −2 and a low Tafel slope of 68.78 mV dec −1 . By comparing the performance of Fe 3 O 4 -FeSe/CoSe 2 with pure CoSe 2 and Fe 3 O 4 -FeSe, it demonstrates to be the most efficient OER catalyst. Significantly, the hierarchical structural strategy of fixed Fe 3 O 4 growth on carbon cloth arrays introduces a new concept to explore the design of high efficiency OER electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2011
·Vol. 13
·期 17
·5460-5466
·
IF 4.006
Manying Liu,Lizhi Zhang,Kewei Wang,Zhi Zheng
The Kirkendall effect has gained intense attention and wide acceptance in nanoscience and nanotechnology because it can result in porosity or deformation in the case of the alloying or oxidation of metals. In this work, we report a facile approach to prepare δ-Bi2O3 solid spheres and further convert them to hierarchical BiOI nests for the first time through a solvothermal reaction at low temperature. The δ-Bi2O3 and BiOI samples obtained were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The formation mechanism has been proposed by emphasizing the Kirkendall effect. We also found that the template of δ-Bi2O3 solid spheres was initially formed by surfactant oleylamine induction. Anion exchange has been confirmed to occur in the reaction involving the Kirkendall effect.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
SOLID STATE SCIENCES
·
2020
·
IF 2.434
Meng Chao,Lijiang Zhao,Jin Leng,Xinghua Liu,Yutong Li,Junying Zhang,Zilong Tang
Tin oxide (SnO 2 ) with high specific capacity and excellent safety performance has become potential candidate for next generation lithium-ion batteries (LIBs). However, the practical application of SnO 2 is hindered by large volume change and particle aggregation. Herein, a type of three-dimensional (3D) hierarchical porous titanium-based microclews composed of one-dimensional (1D) titanium dioxide (TiO 2 ) nanoribbons and SnO 2 nanoparicles, is synthesized for the first time with the assistance of cationic surfactant , cetyltrimethylammonium bromidewere (CTAB). SnO 2 nanoparticles distribute uniformly on the nanoribbons, and CTAB as growth controller plays a key role in the formation of the uniform and stable hierarchical-structure. The as-synthesized CTAB assisted hierarchical-structure TiO 2 @SnO 2 microclews (CA–TiO 2 @SnO 2 MCs) elelctrode demonstrates outstanding ionic conductivity due to the structure assisting efficient contact between electrode and electrolyte, with a remarkable discharge capacity of 448.3 mAh g −1 after cycling for 500 times at a current density of 500 mA g −1 , and a capacity retention of 558.8 mAh g −1 at 200 mA g −1 after 400 cycles in LIBs.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS
·
2019
·Vol. 57
·期 8
·421-430
·
IF 2.596
Guohui Zhang,Panpan Wang,Xiaoxiao Zhang,Chunhui Xiang,Lili Li
Superhydrophobic polycaprolactone (PCL) membranes with hierarchical structure were fabricated via alternate electrospinning/electrospraying techniques. Electrospun PCL/methyl silicone oil (PCL/MSO) nanofibers were employed as substrate. PCL/MSO-PCL microspheres (PCL/MSO-PCL MS ) hierarchical membrane was prepared via electrosprayed PCL MS as an additional layer on the substrate. Field emission scanning electron microscopy images showed the formation of hierarchical PCL/MSO-PCL MS membranes. Compared to pure PCL fibers substrate (120 ± 1.3°), the water contact angle (WCA) of MSO-modified PCL membrane was 142 ± 0.7°. The most interesting observation was that the WCA of PCL MS without any modification could be achieved to 146 ± 2.8°. On this basis, PCL/MSO-PCL MS hierarchical membrane possessed superhydrophobic surface with 150 ± 0.6° of WCA. The excellent surface roughness and air-pocket capacity of hierarchical membranes would make the membranes more hydrophobic. The maximum oil ( n -hexane) adsorption capacity of PCL/MSO-PCL MS membrane was 32.53 g g −1 . Oil–water separation efficiencies of the superhydrophobic membranes were all higher than 99.93% after 10 cycles. The hierarchically structured PCL superhydrophobic membranes indicate the potential applications of environmentally friendly biopolymers as separation membranes. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57 , 421–430
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Weikang Wang,Haotian Xu,Weiwei Zhao,Junde Zhao,Mengyue Jiang,Shujuan Liu,Wei Huang,Qiang Zhao
Flexible free-standing electrode with special hierarchical structure have received widespread attentions due to the increased specific surface area, shortened transport path of electrolyte ions and accelerated ion transmission. Herein, for the first time, the flexible free-standing three-dimensional (3D) flower-like polypyrrole/5,10,15,20-tetrakis(4-carboxylphenyl)porphyrin copper (II) (TF-PPy/Cu-TCPP) nanocomposite electrode with hierarchical PPy micro-flower arrays on the surface has been fabricated via the combination of electrophoretic deposition and electrochemical polymerization. The growth mechanism is involved in the following aspects. I) The wrinkled Cu-TCPP nanosheets provide abundant porous channels to facilitate the immersion of pyrrole molecules and uniform cross-linking of PPy. II) The rough surface of the PPy/Cu-TCPP composite film provides rough sites for the growth of hierarchical TF-PPy arrays under the assistance of H 2 bubbles. The collaborative advantages of 3D conductive networks and the hierarchical TF-PPy arrayed on the rough surface of electrode facilitate the fast ion/electron transport for the enhanced electrochemical performances. The corresponding TF-PPy/Cu-TCPP electrode shows an areal capacitance of 593 mF cm −2 at 0.5 mA cm −2 , which is superior to the PPy/Cu-TCPP electrode (351 mF cm −2 ) and the pristine PPy (287 mF cm −2 ). The symmetric supercapacitor exhibits the energy density of 5.94 μW h cm −2 at a highest power density of 25 μW cm −2 . This work will further enrich the valuable design concepts of flexible free-standing electrode with hierarchical structure for energy storage and conversion.
研究领域:
材料科学
·
电化学
·
能源存储与转换
✓ 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）