SENSORS AND ACTUATORS A-PHYSICAL
·
2025
·
IF 4.9
Pengfei Zhao,Jijun Ding,Haixia Chen,Haiwei Fu
Wearable devices have great potential for development in the fields of human health detection and human-computer interaction due to its flexibility and portability. In this work, Firstly, the resistance response performance of paper/Cu/Al 2 O 3 to temperature is optimized by changing the sputtering time of Al 2 O 3 . Combining the resistance change and stability after one month, paper/Cu/Al 2 O 3 films with 1 min Al 2 O 3 layer is selected. Then, temperature sensor based on optimized paper/Cu/Al 2 O 3 and graphene/PVDF composite temperature-sensitive layers is fabricated. The sensor shows negative temperature coefficient, high temperature response and stability, which provides significant advantages in the field of temperature monitoring. The fastest response/recovery time of the sensor is 1.4 s and 10.48 s respectively, which is fast and reliable in capturing the temperature changes and thus has the capability of real-time temperature monitoring. Another outstanding feature of the sensor is its high linearity to temperature fluctuations (R 2 =0.947). This feature suggests that the sensor enables real-time resistance-temperature interaction. In addition, its practical applications will be explored. The sensor can quickly sense the temperature of fingers, hot water, and working mobile phones. At the same time, the excellent performance of the sensor enables it to achieve the function of illuminating the LED. It lays the foundation for the application of temperature sensors in flexible wearable device applications.
研究领域:
材料科学
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电子工程
·
健康检测
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Zelong Wang,Yanan Zhang,Jungang Yi,Ning Cai,Jia Guo
Heat accumulation has emerged as a critical issue that affects the performance and reliability of modern electronic devices in their evolving toward miniaturization, high power density and high integration. The application of thermal interface materials (TIMs) as a thermal management strategy is commonly employed to tackle this problem. Herein, we report the development and characterization of highly thermally conductive but electrically insulating Cu@Al 2 O 3 /epoxy composites. Stemming from the excellent thermal conductivity of Cu, the Cu@Al 2 O 3 /epoxy composites exhibit thermal conductivity of 1.32 W/m·K at 10 vol% filler content , which is nearly 7 times higher than that of the epoxy resin . Simultaneously, the Cu@Al 2 O 3 /epoxy composites still retain a high electrical resistivity of 2.3 × 10 13 Ω·cm, which is 6 orders of magnitude greater than that of Cu/epoxy composites without Al 2 O 3 barrier layers, because the dense nanoscale insulating Al 2 O 3 shell effectively inhibits the electron transfer . In addition, the Cu@Al 2 O 3 /epoxy composites possess lower dielectric constant and dielectric loss , and better mechanical properties than those of Cu/epoxy composites.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Lijun Yue,Wanjun Zhao,Jinfang Li,Ruifang Wu,Yongzhao Wang,Hongxi Zhang,Yongxiang Zhao
The impact of Indium (In) doping upon the catalytic performance of Pd-Cu/Al 2 O 3 for carbon monoxide preferential oxidation (CO-PROX) in hydrogen (H 2 ) rich atmosphere at low temperature has been studied. A series of catalysts with extremely low palladium (Pd) loading (0.06 wt%) are synthesized by the facile co-impregnation method. When the In/copper (Cu) atomic ratio equals 0.25, Pd-Cu-In 0.25 /Al 2 O 3 can keep 40% CO conversion and 100% carbon dioxide (CO 2 ) selectivity at least 120 min at 30 °C, which is significantly superior to the catalytic performance of Pd-Cu/Al 2 O 3 . The elaborate characterization findings reveal that the added In species to Pd-Cu/Al 2 O 3 causes Indium oxide (In 2 O 3 ) to generate, which produces the interaction of In 2 O 3 with Pd-Cu/Al 2 O 3 , further promoting the dispersion of copper chloride hydroxide (Cu 2 Cl(OH) 3 ). Moreover, the modification of In facilitates the re-oxidation of Pd 0 to Pd + through reducing the formation of palladium hydride (PdH x ) during the CO-PROX reaction. Meanwhile, the addition of In leads to the decrease of Cu + electron cloud density, making it easier to be oxidized to Cu 2+ . Collectively, the easy re-oxidation of Pd 0 and Cu + is favorable to fulfill the Wacker cycle between Pd and Cu species, thus improving the catalytic performance for CO-PROX.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2019
·Vol. 21
·期 3
·606-613
·
IF 9.405
Zhenbing Xie,Bingfeng Chen,Haoran Wu,Mingyang Liu,Huizhen Liu,Jianling Zhang,Guanying Yang,Buxing Han
Transformation of biomass or biomass-based feedstocks into fuels or valuable chemicals is of great importance for the sustainable development of our society. Mesoporous Al2O3–ZrO2 with different Al : Zr molar ratios was prepared by the sol–gel method, and Cu–Ni/Al2O3–ZrO2 catalysts were fabricated by the impregnation method. The catalytic performances of the bifunctional catalysts were studied in the selective hydrogenation of levulinic acid (LA) into 2-methyltetrahydrofuran (MTHF). It was demonstrated that both Cu : Ni and Al : Zr ratios affected the selectivity to MTHF significantly. The bimetallic catalysts Cu–Ni/Al2O3–ZrO2 containing 10 wt% Ni and 10 wt% Cu gave 99.8% MTHF selectivity at full conversion of LA when the Al : Zr ratio was 9 : 1. The outstanding catalytic performance of the catalyst is related to the mesoporous structure, the acidic properties of the support and the synergistic effect between Cu and Ni. The catalyst could be reused five times without a considerable loss of catalytic activity and selectivity.
研究领域:
化学工程
·
催化科学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Shanguang Xu,Xin Han,Fan Zhang,Zhengyang Sun,Ruiying Chai,Fei Xu,Shanguo Du,Xiuling Jiao,Dairong Chen,Jie Zhang
The development of efficient catalysts for the selective hydrogenation of furfural (FAL) to furfuryl alcohol (FOL) is of great importance for sustainable chemical production. In this study, a highly efficient Cu/Al 2 O 3 catalyst was developed for the selective hydrogenation of FAL to FOL, achieving 100 % conversion and 100 % selectivity at 85 °C and 1.0 MPa H 2 with the optimal 7Cu/Al 2 O 3 -AIP catalyst, which was tailored by modulating the surface acidity of Al 2 O 3 and the distribution of Cu species. Evaluation of Cu-supported varying Al 2 O 3 catalysts revealed a near-linear correlation between the density of medium-strong acidic sites and catalytic activity, unequivocally demonstrating that medium-strong acidic sites on the alumina surface serve as the active sites for the reaction, which was further corroborated by competitive adsorption experiments involving pyridine and furfural. Furthermore, the density of Cu 0 sites was varied by adjusting the copper loading and conducting N 2 O selective oxidation experiments. Notably, a linear increase in catalytic activity was observed with the Cu 0 /(Cu 0 + Cu + ) ratio on the catalyst surface. Advanced characterization techniques, combined with experimental results, elucidated that the Cu 0 species act as the primary active sites for H 2 activation, while acidic sites are crucial for FAL adsorption, leading to the exceptional catalytic performance by the synergistic catalysis. This study underscores the synergistic effect between Cu 0 species and acidic sites, providing profound mechanistic insights into the FAL hydrogenation process and establishing a strategic foundation for the rational design of highly efficient Cu-based catalysts.
研究领域:
催化
·
化学工程
·
可持续化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yongzhen Gao,Jingpeng Hu,Wen-Jing Yi,Jingyi Yang,Kai Jiang,Tao Yang,Zhihan Li,Meng Zhang,Zhongyi Liu,Benlai Wu
Support crystal phase plays a crucial role in the controlled C O hydrogenation over the supported catalysts. Herein, the effects of Al 2 O 3 crystal phase (α, θ, η, and γ) on the supported Cu-based catalyst is highlighted for furfural (FAL) hydrogenation to furfuryl alcohol (FA). The evaluation results show that Cu/η-Al 2 O 3 exhibits the best performance (FAL conversion: 99.7 %, FA selectivity: 94.0 %), highest TOF value (29.3 h −1 ) and lowest apparent activation energy (66.3 kJ/mol). The comprehensive characterizations unravel that Cu/η-Al 2 O 3 has the smallest Cu nanoparticles and the highest content of Cu + and Cu 0 , which facilitates H 2 dissociation and FAL adsorption. The reaction mechanisms suggest that Cu/η-Al 2 O 3 has the strongest FAL adsorption and FA desorption capacity. Moreover, it is demonstrated that FAL is linear chemical adsorption on the catalyst surface in the η 1 (O) configuration, which avoids the furan ring hydrogenation, and thereby, results in the high FA selectivity. This work would provide some references for developing the high-efficiency C O hydrogenation catalysts.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Shuyu Qi,Zilong Zhao,Yingqing Ou,Lu Liu,Yatao Ren,Wenyi Dong,Hongjie Wang,Zigong Ning
In this study, a calcium-rich biochar (CRB)-enhanced dual reaction center (DRC) Fenton-like catalyst, Cu-Al 2 O 3 -CRB, was synthesized for the decomplexation of a typical heavy metal complex pollutant, Ni-ethylenediaminetetraacetic acid (Ni-EDTA), in industrial wastewater. After a 90-minute reaction, the removal rate of Ni(II) could reach 95.2%, regardless of the initial solution pH. Various characterization analyses confirmed the formation of electron-rich Cu regions and electron-deficient Al and C regions in the Cu-Al 2 O 3 -CRB catalyst. The catalytic oxidation experiments, chronoamperometry tests, and reactive oxygen species (ROSs) detection further revealed the roles of biochar and CaCO 3 on the catalytic behavior of Cu-Al 2 O 3 -CRB catalyst. The presence of biochar not only enhanced the loading of Cu species but also introduced additional electron transfer channels, while CaCO 3 further interacted with biochar/Cu species to amplify the electron cloud density surrounding Cu. The improvement of electronic polarization facilitated the activation of H 2 O 2 and the generation of •O 2 – , 1 O 2 and •OH. Contrary to conventional interfacial reactions, the weak adsorption between Cu-Al 2 O 3 -CRB and Ni-EDTA due to the electrostatic repulsion, led to the decomplexation reactions primarily occurring in the solution phase, rather than on the catalyst surface. This study sheds light on the potential of Cu-Al 2 O 3 -CRB as a DRC catalyst and emphasizes the significance of contaminant properties when using this kind of catalysts.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2019
·
IF 3.019
Kai Xu,Xiaohong Chen,Honglei Zhou,Liming Bi,Shaoli Fu,Wei Li,Xinkuan Liu,Fengcang Ma,Ke Zhang,Ping Liu
CNTs/Cu-Al 2 O 3 composite powders were successfully synthesized by in situ CVD using Cu-Al 2 O 3 composite powders obtained by internal oxidation of Cu-Al alloy powders. The multi-walled CNTs are obtained without agglomeration and stand on the surface of the composite powders. One end of the CNTs is well bound to matrix. The Cu nanoparticle was the catalyst for the growth of CNTs on the composite powders and Al 2 O 3 on the surface of the Cu-Al 2 O 3 powder plays a key role in the growth process.
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
BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Tan Li,Linjia Yin,Wenhao Xu,Yi Zhang,Hong Xian,Frederik Ronsse,Zhenglong Li,Michael Cordon,Kaige Wang
The production of aviation biofuel precursors from biomass-derived ketones by heterogeneous catalysis has been hindered by the low catalytic activity. Herein, a series of Cu-doped metal oxide catalysts were prepared for the conversion of biomass-derived ketones to aviation biofuel precursors. Solvent-free cyclopentanone conversion via aldol condensation reached 91.1 % over Cu/Al 2 O 3 with 100 % selectivity toward dimer and trimer oxygenated species, all of which are aviation biofuel precursors. This catalyst primarily contains Cu 2 O and Cu nanoparticles which are uniformly dispersed across the Al 2 O 3 surface. From in situ DRIFTS and DFT results, the incorporation of Cu species onto Al 2 O 3 not only increased the diversity of Lewis acidic sites, but also changed the adsorption of C = O groups, which lead to the increased aldol condensation activity of Cu/Al 2 O 3 . This study provides insight on the design of heterogeneous catalysts suitable for the solvent-free synthesis of aviation biofuel precursors from biomass-derived ketones.
研究领域:
催化
·
生物燃料生产
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2023
·
IF 9.8
Tan Li,Jing Su,Linjia Yin,Xiangkun Zhang,Cong Wang,Xinbao Li,Jing Zhang,Kaige Wang
A Cu-based catalyst was developed for one-step solvent-free synthesis of aviation biofuel from biomass-derived ketones, including acetone, cyclopentanone, cyclohexanone, and 2-pentanone. Under the optimal working conditions, the conversion rate of acetone, cyclopentanone, cyclohexanone and 2-pentanone of 100% can be achieved by using Cu/Al2O3. 79.7 c% maximum carbon yield of liquid hydrocarbons with 89.5% selectivity of aviation biofuel was obtained under the conditions of 1.0 MPa H2, 280 °C, and 2 h−1 WHSV. The effects of the calcination temperature on the acidity and basicity of the catalyst, as well as the valence and dispersion of Cu species, were investigated. Based on DFT calculations and in situ DRIFTS results, the preferred adsorption of carbonyl groups and efficient dissociation of hydrogen on Cu+ increased the local concentration of H and feedstock on the catalyst surface, accelerating the rate-determining step that predominated on Cu0. The synergistic effect of Cu0 and Cu+ enhanced the formation of aviation biofuel.
研究领域:
催化
·
化学工程
·
可再生能源
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2018
·
IF 4.521
Zihao Zhang,Changxue Wang,Xin Gou,Hao Chen,Kequan Chen,Xiuyang Lu,Pingkai Ouyang,Jie Fu
A series of Cu-based catalysts with different supports were synthesized and studied for the in situ hydrogenation of 5-hydroxymethylfurfural (5-HMF) to dimethylfuran (DMF) using methanol as an economical hydrogen donor. The structures and properties of the four catalysts (Cu/Al 2 O 3 , Cu/ZnO, Cu/ZrO 2 , and Cu/CeO 2 ) were characterized using X-ray diffraction (XRD), temperature-programmed reduction (H 2 -TPR), and temperature-programmed desorption of ammonia (NH 3 -TPD). The experimental results showed that the use of different supports for the Cu-based catalysts significantly influenced their activity for both H 2 production from methanol and hydrogenation of 5-HMF. The catalyst Cu/Al 2 O 3 showed the best catalytic activity, which can be attributed to the highest activity for the in situ H 2 production from methanol, smallest Cu crystallite size, and strongest acidity. The effects of the substrate concentration, catalyst loading, and reaction temperature and time on the in situ hydrogenation of 5-HMF were systematically investigated to determine the optimum reaction conditions.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2018
·Vol. 8
·期 23
·6091-6099
·
IF 5.365
Danxin Hu,Hualei Hu,Hao Zhou,Guozheng Li,Chunlin Chen,Jian Zhang,Yong Yang,Yaoping Hu,Yajie Zhang,Lei Wang
The highly efficient selective hydrogenation of 5-hydroxymethylfurfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) was achieved in a fixed-bed reactor by using inexpensive potassium-doped Cu/Al2O3 catalysts, which were prepared via a successive incipient wetness impregnation method. The characterization results revealed that the introduction of potassium could adjust the size of the copper particles and modify the acid–base property of the catalyst, leading to a significant change in its performance for the selective hydrogenation of HMF to BHMF. The highest yield of BHMF (98.9%) was obtained over the 1.5K–Cu/Al2O3 catalyst under the reaction conditions of 120 °C, 2.0 MPa of H2, and a weight hourly space velocity (WHSV) of 1.0 h−1. The excellent performance could be explained by the fact that the addition of an appropriate amount of potassium facilitated the dispersion of copper and reduced the acidity of the catalyst, which improved the catalytic activity and suppressed unwanted side reactions, respectively.
研究领域:
催化化学
·
可再生能源化学
✓ 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）