SENSORS
·
2019
·Vol. 19
·期 4
·830
·
IF 3.031
Jing Han,Dong Li,Chunmao Zhao,Xiaoyan Wang,Jie Li,Xinzhe Wu
A thin film of polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) has good flexibility and simple preparation process. More importantly, compared with PVDF, its piezoelectric β-phase can be easily formed without mechanical stretching. However, its piezoelectricity is relatively lower. Therefore, at present, PVDF-TrFE is always compounded with other kinds of piezoelectric materials to solve this problem. The effect of nano-ZnO doping amount on the sensing characteristics of the piezoelectric films was studied. PVDF-TrFE/nano-ZnO films with different nano-ZnO contents were prepared by spin coating process and packaged. The dispersion of nano-ZnO dopants and the crystallinity of β-phase in piezoelectric films with different nano-ZnO contents were observed by scanning electron microscopy and X-ray diffraction, and the piezoelectric strain constants and dielectric constants were measured, respectively. The effect of different nano-ZnO contents on the output performance of the piezoelectric sensor was obtained by a series of impact experiments. The results show that the piezoelectric strain constant and dielectric constant can be increased by doping nano-ZnO in PVDF-TrFE. Moreover, the doping amount of nano-ZnO in PVDF-TrFE is of great significance for improving the piezoelectric properties of PVDF-TrFE/nano-ZnO thin films. Among the prepared piezoelectric films, the output voltage of PVDF-TrFE/nano-ZnO piezoelectric sensor with 7.5% nano-ZnO doping amount is about 5.5 times that of pure PVDF-TrFE. Thus, the optimal range of the doping amount for nano-ZnO is about 4–10%.Keywords:piezoelectric;PVDF-TrFE;nano-ZnO;flexion sensor
研究领域:
材料科学
·
传感器技术
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2025
·
IF 5.5
Juanjuan Yang,Dandan Shao
CO2 to methanol is considered a promising method for CO2 conversion and utilization, yet achieving desirable selectivity remains a significant challenge. Herein, efficient CO2 hydrogenation to methanol is achieved by synthesizing Co0.7ZnO with abundant oxygen vacancies (Ov) through the incorporation of a portion of Co into nanoscale ZnO. By tuning the molar ratio of Co/(Co+Zn) in CoxZnO to increase the Ov content to 71%, CO2 adsorption and activation to form formate (COOH*) are enhanced, thereby reducing the CO selectivity. The efficiency of the hydrogenation of CO2 to methanol was optimized with Co0.7ZnO, which exhibited an impressive methanol formation rate of 2.1 mmol/(g h) and a selectivity of up to 96.7%. The unique structure of incorporating partial Co into nanoscale ZnO to increase the level of Ov not only reduces the level of CO selectivity but also inhibits methane formation, thereby contributing to the high methanol selectivity. This study presents an innovative strategic design through partial doping, which is essential for controlling the selectivity of target products in the CO2 hydrogenation.
研究领域:
化学工程
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2016
·Vol. 24
·期 6
·5179-5188
·
IF 2.76
Sun Jianzhang,Gao Baoyu,Zhao Shuang,Li Ruihua,Yue Qinyan,Wang Yan,Liu Siqi
It is confirmed that nano-ZnO (nZnO) has impact on environment and is considered as heavy metal pollutants. It is a new technology that applies coagulation process to simultaneous removal of the nanoparticles and heavy metals. Environmental chemical behavior of ZnO in water, such as the dispersion, aggregation, sedimentation, and dissolution of releasing metal ions, has been systematically studied in this paper. The result shows that three kinds of nZnO state such as compacted sediment, suspended, and released is separately 36.54 %, 40.61 %, and 22.86 %. Enteromorpha polysaccharide (Ep) was used together with polyaluminum chloride (PAC) in surface water purification. In order to study the mechanism of simultaneous removal of residual nZnO particles and Zn 2+ , coagulation process was further applied in this study. The evolution of flocs size, strength, and recovery ability and fractal structure due to Ep addition was systematically studied in this paper. Results indicated that PAC-Ep was efficient in removing nZnO and Zn 2+ , which leads to more than 95 % particles, 50–60 % natural organic matter (NOM) removed, and 35 % of resolved heavy metal ion adsorbing-chelation. Ep was an efficient coagulant aid in enhancing performance of coagulation and generating flocs with bigger sizes, faster growth rates, and higher recovery abilities. Additionally, the flocs formed by PAC-Ep presented a much looser structure than flocs formed only by PAC.
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研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Xuejuan Niu,Zhiyu Cheng,Zheng Lin
Epoxy resin is widely used in fiber-reinforced composite structures, but its application in high-end projects is limited due to the relatively brittle characteristics caused by its high crosslink density. In this paper, the reaction process of ZnO surface treated with silane coupling agent is described, and the toughening mechanism of nano-ZnO on resin matrix is elaborated. A three-level three-factor experimental strategy has been designed, and orthogonal experimental tests were conducted to investigate the influence of different design parameters, such as solid–liquid epoxy resin ratio (SLR), mass contents of nano-ZnO and catalytic agent (2E4MI). With the results of three-point bending (3P-bending) tests and hardness tests of the beams prepared with twill woven fabrics, surface response analysis based on statistics was carried out to evaluate and optimize design parameters. Results show that, for the beam with the optimized configuration, the maximum bending load, bending stiffness, and hardness were increased by 40.02%, 51.25%, and 58.18%, respectively.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Natural Fibers
·
2024
·
IF 2.8
Zhihui Sui,Zhian Guo,Yaping Li,Qi Zhang,Xin Zhao,Bin Zu
With nano-ZnO, methyl methacrylate (MMA), ethyl acrylate (EA), and dodecafluoroheptyl methacrylate (DFMA) as reaction monomers, potassium persulfate as initiator, nano-ZnO/fluorine polyacrylate linen fabric finishing agent was prepared by semi-continuous seed emulsion polymerization to improve the hydrophobicity and anti-fouling performance of linen fabric. The structure and properties of the film and the finished fabric were characterized and analyzed by1HNMR, FT-IR, and TG. The results showed that the nano-ZnO/fluorine emulsion was successfully prepared with a particle size of about 46 nm, which was combined with linen. The contact angle of the finished linen fabric to water was 130.33°, which indicated that the finished linen fabric had good hydrophobicity. Meanwhile, the anti-fouling performance of the finished linen fabric was also improved. The introduction of nano-ZnO and organic fluorine in turn made linen fabric had the properties of the heat-resistant stability, UV resistance, antibacterial properties, and yellowing resistance.
研究领域:
材料科学
·
纺织工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2023
·Vol. 44
·期 9
·6083-6096
·
IF 5.2
Jingyi Nie,Jianfei Liao,Danni Wang,Meiyun Zhang,Zhaoqing Lu,Bin Yang
Aramid materials have been applied in many important civil and military fields. But a major drawback to aramid materials is the susceptibility to UV-induced damage. In this work, aramid nanofibers (ANFs) and ANF/nano-ZnO composites were used to protect aramid materials from UV-induced damage. ANF protective layer was created on the surface of aramid fibers, and the ANF-coated aramid fibers could be further prepared to aramid paper. Moreover, ANF/nano-ZnO composites were synthesized and used for stronger UV-blocking ability. ANFs provided effective protection to aramid material. The properties after UV exposure (about 9.3 years in the natural environment) were largely improved: ANFs improved the retention rate of strength by 17.96% for aramid fibers and by 16.93% for aramid paper. ANFs also showed synergistic effect with UV-absorbing inorganic nanoparticles. After UV exposure, the tensile strength of aramid paper with ANF/nano-ZnO composites was even higher than the initial value (121.55%), and the retention rate of strength was 2.43 times higher than the original aramid paper.
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
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 4
·040505
·
IF 3.721
Longfei Qin,Zuoyi Xiao,Shangru Zhai,Shifu Wang,Haisong Wang,Guoxiang Wang,Weijie Cai,Zhongcheng Li,Qingda An
Biomass-derived hierarchical porous carbons have attracted considerable attention due to their low cost, environmental friendliness and sustainability. However, the preparation of porous carbon with typically hierarchical pores is still challengeable. In this work, a facile and efficient strategy was proposed to obtain alginate-derived porous carbon by a combination of hard-template and chemical-activation technique. During the fabrication process the nano-ZnO particles displayed triple functions: (a) The nano-ZnO particles were behaved as the hard template to generate more pores. (b) ZnCl2 derived from the nano-ZnO particles acted as a cross-linking agent for obtaining zinc alginate (Zn-SA) hydrogel beads. (c) ZnCl2 was also employed as an activating agent to form micropores during the high-temperature carbonization process. As a subsequence, the obtained carbon exhibited well-developed hierarchical porous structure with high specific surface area of up to 2589 m2 g−1. Due to the high specific surface area, good electrical conductivity and synergistic effect among the typically hierarchical pores, the PC-ZnO-ZnCl2-650 exhibited a high specific capacitance of 316 F g−1 at the current density of 0.5 A g−1 and excellent cycling stability with capacitance retention of 94.4% at 5 A g−1 over 5000 cycles. This ingenious synthesis strategy can provide a new way for efficient preparation of hierarchical porous material.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Xiaofan Qin,Jing Chen,Haiyang Dai,Yang Yang,Guilin Song,Renzhong Xue,Tingting Zhang,Tao Li
Three series of polyimide (PI)/ZnO composite films were prepared and how their dielectric and energy storage performance is affected by particle size of the nano-ZnO fillers for the films has been systematically investigated. The EDS findings indicate that nano-ZnO particles tend to aggregate in the PI matrix with the increasing ZnO-doping amount, and the nano-ZnO particles with smaller size are more likely to aggregate with the same doping amount due to their higher activity. Profiting from the interface polarization effect between PI matrix and nano-ZnO fillers, the dielectric constant can be improved by incorporating an appropriate number of nano-ZnO fillers, but reduced by excessive doping due to the aggregation of nano-ZnO particles. The experimental results show that the dielectric properties and breakdown strength of these films are closely related to nano-ZnO particle size. For instance, the dielectric constant reaches the maximum value when the content of ZnO-30nm fillers is 0.1 wt %, but mounts to the maximum values as the fillers content for ZnO-50nm and ZnO-90nm is 0.2 wt %. The breakdown strength of PI/ZnO composite films shows a decreasing trend with increasing ZnO-30nm fillers content, while a trend of first increasing and then decreasing with increasing ZnO-50nm and ZnO-90nm fillers content, reaching the highest value when the doping amount is 0.2 wt%, respectively. The PI/ZnO-90nm films exhibit the optimal energy storage performance, and the film with 0.2 wt % ZnO content shows an U d of 4.05 J·cm −3 with an energy efficiency of 75 % under electric field strength of 425 kV/m. Positron annihilation lifetime spectroscopy (PALS) has been applied to study the free volume characteristics, and the correlation between interface free volume and electrical breakdown performance of PI/ZnO films has been explained.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2017
·Vol. 4
·期 2
·025605
·
IF 1.068
Xiaoqing Dai
Nano ZnO enhanced 3D porous reduced graphene oxide (RGO) with superior electromagnetic interferece (EMI) shielding efficiency (SE) was fabricated through a UV enhanced hydrothermal process. In this study, a composite with 10 wt% of 3D-RGO/ZnO was tested in a broadband frequency range from 2 to 18 GHz. Under the whole test conditions, the ratio of SEA/SET is higher than 50% and the maximum value can reach to 94%, indicating the shielding mechanism mainly attributes to absorption. The EMI SE showed that the thinnest thicknesses to shield different frequency range are 0.7 mm for 10 dB, 1.6 mm for 20 dB and 3.7 mm for 30 dB, which suggests 3D-RGO/ZnO could meet the requirement of new generate EMI shielding material.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2022
·
IF 4.778
Hengyang Zhang,Miao Yu,Yang Du,Liang Xu,Deping Ma,Qun Wang
Developing a flexible nano-composite material which is not only impermeable to low-polar oil, but also has the ability of daytime radiation cooling, remains a huge challenge for both academia and industry. By modifying the fiber network of the dust-free paper using nano-ZnO particles (ZnO-DF), we strategically designed and demonstrated dual capabilities of superhydrophilicity/superoleophobicity and daytime radiant cooling for the flexible cellulose nano-composite simultaneously. A superior surface with superhydrophilic/superoleophobic (oil contact angle up to 159° and water contact angle down to 0°) was attained by regulation of surface energy components and roughness. Furthermore, the materials revealed outstanding corrosion and mechanical damage resistance, 152,788 L m −2 h −1 high permeation flux and >99.2% continuous and efficient oil-water separation performance. In addition, a cooling effect of about 5.6 °C of ZnO-DF paper could be achieved by cooperative function of both radiative cooling and sweat evaporation. It is expected that the ZnO-DF paper is promising for the thermal management of wearable products integrated with passive radiant cooling, phase change cooling (e.g., sweat evaporation) and large-scale industrial oil-water separation.
研究领域:
材料科学
·
环境工程
·
热管理技术
✓ 已验证
产品关联
DOI
高影响因子
PLASMA SCIENCE & TECHNOLOGY
·
2023
·Vol. 25
·期 10
·104004
·
IF 1.7
Qijun DUAN,Yanze SONG,Shuai SHAO,Guohua YIN,Haoou RUAN,Qing XIE
The surface flashover of epoxy resin (EP) composites is a pivotal problem in the field of high-voltage insulation. The regulation of the interface between the filler and matrix is an effective means to suppress flashover. In this work, nano ZnO was fluorinated and grafted using low-temperature plasma technology, and the fluorinated filler was doped into EP to study the DC surface flashover performance of the composite. The results show that plasma fluorination can effectively inhibit the agglomeration by grafting –CFx groups onto the surface of nano-ZnO particles. The fluorine-containing groups at the interface provide higher charge binding traps and enhance the insulation strength at the interface. At the same time, the interface bond cooperation caused by plasma treatment also promoted the accelerating effect of nano ZnO on charge dissipation. The two effects synergistically improve the surface flashover performance of epoxy composites. When the concentration of fluorinated ZnO filler is 20%, the flashover voltage has the highest increase, which is 31.52% higher than that of pure EP. In addition, fluorinated ZnO can effectively reduce the dielectric constant and dielectric loss of epoxy composites. The interface interaction mechanism was further analyzed using molecular dynamics simulation and density functional theory simulation.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2016
·
IF 3.349
Xiaojun He,Zide Liu,Hao Ma,Nan Zhang,Moxin Yu,Mingbo Wu
Shell-like hierarchical porous carbons (SHPCs) were prepared from petroleum pitch by a nano-ZnO-template strategy coupled with in-situ KOH activation technique. The as-made SHPCs feature interconnected thin carbon shells and abundant short hierarchical pores, which are favorable for both the rapid transfer of electrons and ions during the charge-discharge process. The SHPCs made under optimal conditions show a specific surface area up to 2646 m 2 g −1 . As electrodes for supercapacitors , SHPCs exhibit a high specific capacitance up to 296 F g −1 at 0.05 A g −1 in 6 M KOH electrolyte, good rate performance remaining at 237 F g −1 at 20 A g −1 and a good cycle stability with over 96.5% capacitance retention after 5000 cycles. This work suggests a facile strategy for high-efficiency synthesis of SHPCs from petroleum pitch as electrode materials for supercapacitors and other energy stotage devices.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）