Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Jinhui Wang,Ruisong Wang,Xiaoxiao Ji,Chunde Jin,Yutao Yan
Phenol formaldehyde (PF) resin adhesives are widely used in the production of bamboo-based composites owing to their excellent bonding strength and durability. However, the inherent brittleness of cured PF resin may result in notable stress concentration at the interface between PF resin and bamboo bonding, leading to the generation of cracks. In this study, a hyperbranched compound polyethyleneimine (PEI) with high reaction activity was incorporated into a PF resin adhesive to toughen the adhesive and the bonding interface. And the effects of PEI incorporation on the properties of the adhesive and the bonding performance between PF resin and bamboo were comprehensively investigated. The results showed that introduction of flexible PEI chains could effectively facilitated stress transfer, avoiding stress concentration, thus enabling efficient energy release and play a toughening effect. In addition, PEI could react with PF resin and bamboo components during hot pressing, forming a three-dimensional network structure and enhancing the bonding interface, which was proved by FT-IR and XPS analysis. When 1 wt% PEI was incorporated, the bending strength and Charpy impact toughness of the modified PF resin was significantly increased by 38.88% and 76.02%, respectively, compared with the pure PF resin. While the dry and wet shear strength of the bamboo composite bonded by the PEI modified PF resin were also obviously increased. This study is expected to address the problem of cracking in the bonding interface of bamboo composite, and endow the composites with high strength and durability, which can prolong its service life and contribute to the healthy and sustainable development of the bamboo industry.
研究领域:
材料科学
·
木材科学与技术
·
高分子化学
·
复合材料工程
·
胶接与界面科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Yao Zhu,Huan Yi,Qiaoyan Hao,Jidong Liu,Yuxuan Ke,Zhuo Wang,Dianyuan Fan,Wen jing Zhang
Monolayer WS 2 (1L-WS 2 ) possesses direct band gap, which is beneficial for light emitting applications. However, high quality sample obtained via mechanical exfoliation suffers from ultralow yield of large flakes while large 2D material monolayers synthesized by chemical vapour deposition (CVD) unintentionally induce many defects, resulting in low photoluminescence (PL) intensity. Herein, we firstly control the 1L-WS 2 scalable growth through H 2 introduction at the beginning of the CVD synthesis. Its domain size can be increased from 1 μm up to 20 μm with higher coverage, compared to that synthesized without H 2 introduction. Then, we propose scalable ways to anneal the obtained large 1L-WS 2 in Ar diluted hydrogen sulfide (H 2 S) atmosphere at 750 °C or to treat it with (3-mercaptopropyl) trimethoxysilane (MPS). Its PL intensity can be increased to 12 times by H 2 S or more interestingly to 30 times by MPS, respectively. Our systematic analyses show that the drastic PL improvements are mainly attributed to the reduction of structural defects by H 2 S and MPS, which is facilitated via the H– bond in them. The results help to explore routes to obtaining large-size single crystalline transition metal dichalcogenides monolayer (1L-TMDCs) and intense PL emission.
研究领域:
材料科学
·
纳米科技
·
凝聚态物理
·
表面科学
·
半导体材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 47
·期 7
·9083-9089
·
IF 3.83
Hongli Liu,Lantian Zhang,Jing Li,Hongyan Li,Guoqing An,Yajing Li,Zhong Chen
SiBCN ceramic aerogels have excellent properties such as ultra-high temperature stability, low density and high thermal insulation . The aerogels have better potential applications in aerospace and other fields. However, similar to inorganic aerogels , the low mechanical strength of SiBCN ceramic aerogels are the main limitation of its application. Based on the principle of inorganic double network enhancement, the first network was constructed by PVA and HNTs , and HNTs/SiBCN dual network aerogels were constructed by SiBCN ceramic aerogels as the second network. The structure and mechanical properties were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), specific surface area analyzer and pressure tester. Compared with SiBCN ceramic aerogels, 6 wt% HNTs-SiBCN ceramic hybrid aerogels have better microscopic properties (maintaining basic porous network structure and structural stability) and mechanical properties.The continuous HNTs first network can effectively transfer the stress load and enhance the strength of SiBCN ceramic aerogels.
研究领域:
材料科学
·
无机非金属材料
·
纳米复合材料
·
航空航天材料
·
高分子复合材料
✓ 已验证
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Hongsheng Yu,Suhang Chen,Xiaodong Yu,Wei Zhang,Christian Paravan,Luigi T. DeLuca,Ruiqi Shen
The slow regression rate induced by the difficulty of pyrolysis has limited the practical application of hydroxyl-terminated polybutadiene (HTPB)-based fuels for hybrid rocket propulsion. A possible strategy is the use of suitable transition metal elements promoting polymer matrix thermal decomposition of fuels. This paper investigates the effects of nickel acetylacetonate, Ni(acac) 2 , on the thermal stability and combustion of HTPB-based fuel formulations. The presented experimental results show that the addition of Ni(acac) 2 can intensely decrease the thermal stability of HTPB thus enhancing the solid fuel regression rate even at a small additive mass fraction: under an oxygen mass flux of 50 kg/m 2 s, HTPB + 5 wt% Ni(acac) 2 shows a 25.5% increase over the non-loaded baseline. Kinetics analyses reveal that the catalytic effect is mainly induced by the Ni 2+ in Ni(acac) 2 at the early stage of decomposition, and by the NiO produced from the oxidative decomposition of Ni(acac) 2 in the fuel final degradation stage. On the other hand, the addition of Ni(acac) 2 decreases the combustion heat of HTPB-based fuels significantly and implies the accumulation of its decomposition products (much metal Ni, moderate elemental C, and a little NiO.) at the fuel regressing surface. Eventually, when the content of Ni(acac) 2 exceeds 5 wt%, the growth of regression rate slows down rapidly, and a performance detriment occurs at 40 wt%. This study verifies the catalytic effect of Ni(acac) 2 on polymer matrix for HTPB based fuels showing the attractive regression rate performance of this additive.
研究领域:
推进剂化学
·
燃烧学
·
高分子材料科学
·
航天动力工程
·
催化化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Dan Wu,Mengnan Hu,Yongyi Zhang,Jing Zhou,Zhaona Wang
Surface enhanced Raman spectroscopy (SERS) is a key nondestructive detecting technology with a broad application demands. However, relative low stability and homogeneity of the SERS substrate hinder its practical applications. Here, a simple and flexible approach is proposed to achieve the arrayed SERS substrates with the periodicity and local randomness by directly growing silver nanoflowers on the patterned wafer fabricated by the optical interference method. By utilizing the hotspot effect of nanogaps within/between the Ag nanoflowers, the SERS substrates demonstrate the low detecting limit of 5 × 10 −10 M and 5 × 10 −9 M in one-dimensional (1D) and two-dimensional (2D) pattern structures for Rhodamine 6G (R6G) probe molecule, respectively. The periodicity assures the fabricated substrate a promising reproducibility and stability. After the 1D array structure is left for 21 days, the intensity of Raman signal of R6G maintains at 80%. Moreover, the proposed method has the advantages of simple preparation, low cost, flexible tunability, and easy-fabrication large scale substrate. The results indicate that the long-range ordered silver nanoflower array structures are promising candidates for the high performance SERS substrate in chemical analysis, medicine and environment monitoring.
研究领域:
分析化学
·
纳米生物技术
·
材料科学
·
环境监测
·
医学检测
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2015
·
IF 2.999
Chuanying Wang,Xianhua Cheng
β-NaYF 4 :Yb 3+ /Er 3+ microcrystals codoped with Cr 3+ ions were prepared for the first time via a facile hydrothermal method . The influence of doping concentration of Cr 3+ ions on growth and upconversion (UC) luminescence properties of β-NaYF 4 :Yb 3+ /Er 3+ microcrystals were investigated in detail. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra and photoluminescence (PL) spectra were used for characterization. The results demonstrated that the morphology and size of β-NaYF 4 :Yb 3+ /Er 3+ microcrystals were influenced by doping concentration of Cr 3+ ions, the possible mechanism was proposed. The UC intensity of β-NaYF 4 :Yb 3+ /Er 3+ microcrystals was significantly enhanced by doping of Cr 3+ ions. In contrast to β-NaYF 4 :Yb 3+ /Er 3+ microcrystals without doping of Cr 3+ ions, the green and red emission intensities of the microcrystals codoped with 15 mol% Cr 3+ ions were enhanced by 16 and 7 times, respectively. The enhancement of the UC intensities should be ascribed to the distortion of local symmetry around Er 3+ ions, the UC mechanism was discussed. This work will be helpful for improving the UC intensity of other lanthanide-doped UC nano- and micro-crystals.
研究领域:
材料科学
·
无机化学
·
光功能材料
·
纳米医学
·
生物成像
·
分子影像学
·
光学材料
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 32
·46579
·
IF 1.901
Xie Li,Wei Li,Zhiqing Liu,Xiaolin Wang,Heling Guo,Rongjie Wang,Xuhong Guo,Cuihua Li,Xin Jia
Polyurethane (PU) has been widely used as a glue in various areas. However, adhesion in the presence of water is greatly impeded and results in most synthetic adhesive failure. In this study, we designed and synthesized a novel PU construction; underwater PU adhesives were created by the incorporation of synthetic glycerol monomethacrylate (GMA). Furthermore, the urethane structure helped the adhesive eliminate the interfacial water barrier through interactions that were stronger than hydrogen bonding, and GMA as a crosslinking agent was used to generate post-covalent-crosslinking networks through radical polymerization. This enhanced the cohesion so the diffusion of water molecules could be overcome. Fourier transform infrared spectroscopy, thermogravimetric analysis, underwater adhesion measurements, and tensile tests were used to characterize the chemical and mechanical properties of the as-obtained adhesive. This led to an adhesive with a better mechanical strength and interfacial adhesion in water, and the results show that the mechanical properties (tensile strength, Young's modulus, and tensile elongation) of the GMA–PU adhesive were higher than those of the pure PU. As for the 4% GMA, the tensile strength was enhanced by 24.3% and the elongation was enhanced by 125.23% over those of the pure PU. This confirmed that the incorporation of GMA into the PU matrix indeed induced increasing cohesion, and the sample's adhesive strength was 21.19 ± 3.9 MPa; this indicated a superior adhesive strength over that of the pure PU. In addition, we can foresee that underwater adhesion will play an important role in prospective surgery and engineering areas. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46579.
研究领域:
高分子材料
·
生物医学工程
·
粘附科学
·
组织工程
·
医用胶粘剂
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2014
·Vol. 39
·期 9
·4198-4205
·
IF 2.93
Zhenlong Zhang,Jichun Zhu,Shengjun Li,Xiangyang Liu,Yanli Mao
In this paper, TiO 2 nanotube (TNT) arrays and (Cu 2 Sn) x /3 Zn 1− x S ( x = 0.75, 0.24, and 0.09) nanocrystals were prepared, and TiO 2 nanotubes (TNTs) were sensitized with (Cu 2 Sn) x /3 Zn 1− x S nanocrystals. Compared with the plain TNTs, (Cu 2 Sn) x /3 Zn 1− x S sensitized TNTs present an enhanced photoelectrochemical response. The photocurrent enhancement was characterized with the photocurrent ratio of (Cu 2 Sn) x /3 Zn 1− x S sensitized TNTs to plain TNTs, which were 1.50, 1.63, and 2.13 for (Cu 2 Sn) x /3 Zn 1− x S with the composition of x = 0.75, 0.24, and 0.09, respectively. To understand this phenomenon, the energy band alignments of TNTs and (Cu 2 Sn) x /3 Zn 1− x S were investigated, based on which the conduction band offsets (CBO) between TNTs and (Cu 2 Sn) x /3 Zn 1− x S were determined, which were 0.31, 0.47, and 0.63 eV for (Cu 2 Sn) x /3 Zn 1− x S with the composition of x = 0.75, 0.24, and 0.09, respectively. These results display that the photocurrent enhancement becomes large with the increase of CBO, which indicates that the enhanced photoelectrochemical response is mainly due to the energy level matching between TNTs and (Cu 2 Sn) x /3 Zn 1− x S, and the variation of enhancement is resulting from the change of CBO.
研究领域:
材料科学
·
光催化
·
半导体纳米材料
·
能源材料
·
光电化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 15
·8893-8899
·
IF 10.7
Ziming Zhang,Zhiqiang Gao,Tingting Deng,Qingfeng Song,Lidong Chen,Shengqiang Bai
Mg3(Sb,Bi)2-based Zintl compounds have attracted lots of attention due to their high thermoelectric performance and good mechanical properties. However, thermally activated mobility, which is ascribed to the grain boundary scattering, greatly limits their practical use. In this work, we reveal the plasticity of Mg3(Sb,Bi)2-based compounds in the compressive strength test. The ab initio analysis indicates that this plasticity should be ascribed to the low slip barrier energy (∼580 mJ m−2), which is only one third of the cleavage energy (∼1600 mJ m−2). Based on this finding, we propose a cold-deformation procedure to elongate particles and to enhance texture, which successfully suppresses the grain boundary scattering. As a result, a high carrier mobility of 86.6 cm2 V−1 s−1 and a high power factor of 16.2 μW cm−1 K−2 in Mg3.1Bi1.5Sb0.49Te0.01 are obtained at room temperature. The plastic deformation capacity of Mg3(Sb,Bi)2 compounds provides a near-net-forming method to fabricate special-shaped devices at room-temperature, which will extend the application fields of thermoelectric techniques.
研究领域:
材料科学
·
凝聚态物理
·
无机非金属材料
·
热电转换
·
固态物理化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Lichun Ma,Nan Li,Guangshun Wu,Guojun Song,Xiaoru Li,Ping Han,Gang Wang,Yudong Huang
A novel amine-based functionalization method was developed to improve the interfacial adhesion between TiO 2 NWs and CFs in supercritical water. The microstructure, morphology and mechanical properties of CFs were investigated. It was found that introducing hexamethylenetetramine (HMTA) dendrimers and branched polyethyleneimine (PEI) on CF could increase significantly the adhesion strength between CF and TiO 2 NWs and their interfacial shear strength with epoxy resin, and the order is CF-PEI-TiO 2 NWs > CF-HMTA-TiO 2 NWs > CF-COOH-TiO 2 NWs > CF-TiO 2 NW. Meanwhile, the reinforcing mechanisms and interfacial failure modes have also been discussed. We believe that these effective methods may provide theoretical foundation for the preparation of high performance composite materials.
研究领域:
材料科学
·
复合材料界面工程
·
纳米材料修饰
·
高分子基复合材料
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Pingfan Xu,Yaofa Luo,Peikun Zhang
Polyurethane (PU) composites integrated with outstanding fire retardancy, smoke suppression as well as ameliorated mechanical property is attractive, but remains a challenge. Here, we demonstrate the interfacial architecting of organic–inorganic hybrid (ACAPP) by reacting renewable chitooligosaccharide (COS) with ammonium polyphosphate (APP) and ammonium octamolybdate (AOM) via a one-pot, facile and eco-friendly approach. The ACAPP with multiple hydroxyl groups shows good compatibility and strong interfacial adhesion force with PU matrix due to the abundant covalent cross-linking points and hydrogen bonds networks. The incorporation of 15 wt% ACAPP enables the resultant PU composite to achieve a V-0 rating, a limiting oxygen index of 26.1%, 31.1% and 44.8% reduction in total heat release and total smoke production, respectively, far outdistancing conventional APP. The suppressed fire hazards mainly benefits from the synergy catalytic carbonization effect of ACAPP in condensed phase. Moreover, ACAPP reinforces the tensile strength of PU whilst retaining the decent ultimate elongation. This work may offer a referable exemplification for constructing green flame-retardant to balance high fire safety and mechanical properties.
研究领域:
高分子材料科学
·
阻燃化学
·
复合材料工程
·
绿色化学
·
材料界面科学
✓ 已验证
DOI
高影响因子
Laser & Photonics Reviews
·
2024
·Vol. 18
·期 11
·2400151
·
IF 9.8
Jiaoyin Zhao,Jiwen Chang,Nan Wang,Peihang Zhao,Mengyuan Zhu,Ying Liu,Dongxu Guo,Yu Wang,Panlai Li,Zhijun Wang,Hao Suo
Thermal quenching of luminescence materials poses a major obstacle to the technological application of luminescence thermometry. It still remains challenging to attain thermally enhanced light emissions, especially in the second near-infrared window (NIR-II). Herein, an anomalous thermal dependence of NIR-II luminescence in the negative thermal expansion (NTE) Sc 2 Mo 3 O 12 :Er 3+ /Ho 3+ nanocrystals is reported. Mechanistic investigations affirm that Ho 3+ ion can work as an energy reservoir and back-transfer to Er 3+ ion with the assistance of lattice phonon at elevated temperatures. Moreover, the Ho 3+ -mediated energy feedback is strengthened by the thermal contraction between dopant ions, thereby enabling a remarkable thermal enhancement of NIR-II emission over 11-fold. The opposite thermal response of Er 3+ and Ho 3+ emissions is harnessed for NIR-II ratiometric thermometry, registering exceptional performance in a high-temperature regime ( S r = 1.71% K −1 , δT = 0.2 K at 513 K). These findings may inspire new insights for addressing the thermal quenching of NIR-II luminescence, which also raises exciting opportunities for flexible thermometry in complex settings.
研究领域:
材料科学
·
光学材料
·
纳米科技
·
生物医学工程
·
分子成像
·
温度传感
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）