APPLIED CATALYSIS B-ENVIRONMENTAL
·
2018
·
IF 11.698
Suqian Xu,Hanxu Zhu,Wenrui Cao,Zhibin Wen,Jinnan Wang,Corvini Philippe François-Xavier,Thomas Wintgens
Cu-Al 2 O 3 -g-C 3 N 4 and Cu-Al 2 O 3 -C-dots were synthesized for the first time to enhance the catalytic activity and utilization of H 2 O 2 . SEM, TEM, XPS, FT-IR, XRD, TPR and solid-state EPR were used to characterize the catalysts. In the Cu-Al 2 O 3 -g-C 3 N 4 system, the electron-rich centre of Cu and electron-deficient site of Al were formed due to the higher electronegativity of Cu. Moreover, Cu ions could coordinate with the hydroxyl on the tri-s-triazine ring of g-C 3 N 4 or the graphene conjugated π-domains of C-dots via the Cu O C linkage so that the orbital interactions involving electron transport from π → Cu also induced the formation of an electron-rich Cu centre and an electron-deficient π-electron conjugated system, resulting in the strengthening of the dual-reaction centres. This mechanism was validated by Roman, EPR and XPS spectra. In addition, EPR experiments demonstrated that two electron-transfer processes formed OH in the presence of H 2 O 2 . The first electron transfer was from the electron-rich Cu centres to H 2 O 2 , and the other was from H 2 O to the electron-deficient site. Thus, more OH were generated and high H 2 O 2 utilization was achieved in the Cu-Al 2 O 3 -g-C 3 N 4 and Cu-Al 2 O 3 -C-dots suspension. Furthermore, the turnover frequency (TOF) for the Cu-Al 2 O 3 -C-dots and Cu-Al 2 O 3 -g-C 3 N 4 dispersions were determined and were found to be much higher than those of the classic homogeneous Fenton reaction. Thus, Cu-Al 2 O 3 -g-C 3 N 4 and Cu-Al 2 O 3 -C-dots showed high activity and stability for the catalytic degradation of organic pollutants under mild conditions.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
RSC Advances
·
2025
·Vol. 15
·期 6
·4443-4457
·
IF 4.6
Junqi Zhang,Yongwang Li,Zhiwei Zhang,Zheng Wang,Jiaxing Zhang,Shuai Liu,Yang Qin,Bingxin Zhu,Tongxue Zhang,Hongyu Wang,Fumin Wang,Xubin Zhang
The development of simple, efficient and economical catalysts for the hydrogenation of biomass to produce high value-added chemicals is of great significance in solving the energy crisis. In this work, a series of non-precious metal catalysts (Cu–Al2O3–ZnO) with different defect sites were prepared by etching Devarda's alloy. Under optimized mild reaction conditions, the furfural conversion and furfuryl alcohol selectivity are both greater than 99.0%, and the catalyst has good reusability. Characterisation and experiments were used to investigate the activate species for hydrogenation reaction. It can be proved that the low-valent Cu species in the Cu–Al2O3–ZnO catalysts play an important role as adsorption and dissociation sites for H2. Different etching degrees and sample reduction temperatures of the alloy can be used to adjust the content of acidic sites such as Al2O3 and CuO, which have appropriate adsorption properties for furfural. ZnO promotes the dispersion of the Cu species and enhances the accessibility of the active sites. The etching method achieves the interaction between species to further enhance the stability and activity of the catalyst. The catalytic performance of the catalyst is very competitive and this study provides a new method for the efficient hydrogenation of furfural to furfuryl alcohol.
研究领域:
化学工程
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可再生能源
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催化科学
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产品关联
DOI
PubMed
高影响因子
ChemCatChem
·
2022
·Vol. 14
·期 13
·e202200311
·
IF 5.497
Yuyao Zeng,Bowei Wang,Fanyong Yan,Wensheng Xu,Guoyi Bai,Yang Li,Xilong Yan,Ligong Chen
Graphical Through a convenient impregnation method, highly-distributed and stable Cu nanoparticles were dispersed on the boron doped γ-Al 2 O 3 support, which catalyzed continuous reductive amination of levulinic acid to corresponding N-substituted pyrrolidinones. The reductive amination of biomass-derived levulinic acid (LA) to value-added N-substituted pyrrolidinones with amine and molecular hydrogen over heterogeneous catalyst represents an atom-economical and scalable route. In this paper, a series of boron doped Cu/Al 2 O 3 catalysts via kneading and impregnation method are developed for the continuous reductive amination of LA. Compared with Cu/Al 2 O 3 , Cu 10 /AlB 3 O catalyst exhibits greatly improved catalytic performance for this reaction at low operation temperature. Structure-property correlation investigations were performed with diverse characterization methods, and the results revealed that the excellent catalytic performance of boron doped Cu/Al 2 O 3 catalysts was mainly attributed to the synergistic effect of its well-dispersed Cu nanoparticles, appropriate surface Cu electronic state and surface acidic sites nearby. Besides, Cu 10 /AlB 3 O shows great stability during the reaction over 200 h. This work provides a low-cost, efficient and environmentally friendly heterogeneous catalytic system for the continuous production of N-substituted pyrrolidinones.
研究领域:
催化化学
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绿色化学
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生物质转化
✓ 已验证
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 12
·2753
·
IF 4.2
Yongzhen Gao,Wenjing Yi,Jingyi Yang,Kai Jiang,Tao Yang,Zhihan Li,Meng Zhang,Zhongyi Liu,Benlai Wu
The selective hydrogenation of the biomass platform molecule furfural (FAL) to produce furfuryl alcohol (FA) is of great significance to alleviate the energy crisis. Cu-based catalysts are the most commonly used catalysts, and their catalytic performance can be optimized by changing the preparation method. This paper emphasized the effect of calcination atmosphere on the performance of a Cu/Al2O3catalyst for the selective hydrogenation of FAL. The precursor of the Cu/Al2O3catalyst prepared by the ammonia evaporation method was treated with different calcination atmospheres (N2and air). On the basis of the combined results from the characterizations using in situ XRD, TEM, N2O titration, H2-TPR and XPS, the Cu/Al2O3catalyst calcined in the N2atmosphere was more favorable for the dispersion and reduction of Cu species and the reduction process could produce more Cu+and Cu0species, which facilitated the selective hydrogenation of FAL to FA. The experimental results showed that the N2calcination atmosphere improved the FAL conversion and FA selectivity, and the FAL conversion was further increased after reduction. Cu/Al2O3-N2-R exhibited the outstanding performance, with a high yield of 99.9% of FA after 2 h at 120 °C and an H2pressure of 1 MPa. This work provides a simple, efficient and economic method to improve the C=O hydrogenation performance of Cu-based catalysts.
研究领域:
催化化学
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能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Catalysis
·
2022
·
IF 13.7
Xiwen Song,Chengsheng Yang,Xianghong Li,Zhongyan Wang,Chunlei Pei,Zhi-Jian Zhao,Jinlong Gong
Understanding the nature of adsorbates and intermediates on catalytic surfaces is critical for the development of highly efficient systems for CO2 conversion. However, the role of structural hydroxyl groups in CO2 hydrogenation is still under debate. This paper describes an experimental study on the nature of surface-bound hydroxyl groups over Al2O3-supported Cu catalysts for CO2 reduction. A model 5 wt % Cu/Al2O3 catalyst with stable hydroxyl groups was prepared. The structural hydroxyl groups were modulated by the hydration of unsaturated Al3+ sites, which were introduced by the evaporation-induced self-assembly method. Terminal hydroxyl groups (T-OH*) were found to significantly facilitate the conversion of CO2, while the AlVI-T-OH and AlIV-T-OH species promoted the formation of Al-b-HCOO and Al-m-HCOO species, respectively, accompanied with the increase in methanol and dimethyl ether yields. The reaction behavior of hydroxyl species was further investigated by in situ IR experiments with HD isotope exchange on Cu/Al2O3. T-OH* were identified as active sites participating in the formation of key intermediates, while more hydroxyl sites were occupied by formate species with the H coadsorbed on the Cu surfaces.
研究领域:
催化
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化学工程
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表面科学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 10
·期 13
·4412-4423
·
IF 5.721
Qiang Liu,Zhenbo Zhao,Masahiko Arai,Chao Zhang,Ke Liu,Ruhui Shi,Peixuan Wu,Zhuangqing Wang,Weiwei Lin,Haiyang Cheng,Fengyu Zhao
The transformation of γ-valerolactone (GVL) into 1,4-pentanediol (1,4-PDO) and 2-methyltetra-hydrofuran (2-MTHF) in the presence of H2, one of the useful biomass conversion and utilization processes, was investigated with monometallic Cu/Al2O3 and bimetallic ZnCu/Al2O3 catalysts. A 10 wt% Cu-loaded monometallic catalyst produced 1,4-PDO and 2-MTHF in comparable quantities at a medium conversion (∼50%). When Zn was added in a range of Zn/Cu molar ratios of up to 2, in contrast, the catalysts yielded 1,4-PDO in a high selectivity of about 97% at low and high conversion levels. In addition, the 1,4-PDO selectivity over the ZnCu/Al2O3 catalysts remained almost unchanged during recycled runs. That is, the addition of Zn to Cu/Al2O3 switched the product selectivity and improved the catalyst stability and reusability. Furthermore, the physicochemical properties of the catalysts were characterized by several methods including XRD, TEM, TPR, XPS, FTIR of adsorbed pyridine, and so on. On the basis of those results, the relationships between the catalytic performance (activity, selectivity, and reusability) and the catalyst structural features were discussed.
研究领域:
催化化学
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生物质转化
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 45
·46705
·
IF 1.901
Dapeng Gu,Longxiao Zhang,Suwen Chen,Kefeng Song,Shouyao Liu
The filling combination of polytetrafluoroethylene (PTFE)/Cu/Al 2 O 3 filled poly(methyl methacrylate) (PMMA) based composites aiming at low friction and wear is optimized based on L 9 (3 4 ) by Taguchi method. The worn morphologies of PMMA based composites are analyzed by scanning electron microscopy (SEM). The PTFE transfer film and the wear debris on the steel ball surface are analyzed by SEM and X-ray spectroscopy. It is observed that the friction and wear of PMMA can be obviously decreased by filling with PTFE, Cu, and Al 2 O 3 . PTFE has the most significant but Cu has the negligibly smallest contribution on both the friction coefficient and the wear rate. The lower friction coefficient (<0.2) appears by the combination of the mass ratio of PTFE larger than about 4.5% and the mass ratio of Al 2 O 3 lower than ∼7.5%. The lower wear rate (<5 × 10 −5 mm 3 /Nm) appears by the combination of the mass ratio of PTFE larger than about 5% and the mass ratio of Al 2 O 3 lower than ∼8%, but it does not include that PTFE is greater than about 8.5% and Al 2 O 3 is less than about 1.5%. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46705.
研究领域:
材料科学
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机械工程
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Xinyu Zhou,Pin Mao,Huiran Jin,Wanxia Huang,Aotian Gu,Kaiwei Chen,Shan Yun,Jing Chen,Yi Yang
Cu-based functional materials are excellent candidates for the elimination of iodine anions. However, the low utilization rate of Cu and its unsatisfactory adsorption performance limit its large-scale practical applications. This paper proposes a co-gelation method to obtain Cu/Al 2 O 3 aerogels with a high specific area (537 m 2 /g). Cu/Al 2 O 3 aerogels have a hierarchical porous structure and contain a high proportion of Cu (20.5 wt%). The high dispersibility of Cu, which is based on an in-situ gel process, provides conditions for the high-efficiency elimination of iodide anions. We conducted adsorption experiments that demonstrated that the fabricated Cu/Al 2 O 3 aerogel had an ultrahigh adsorption capacity (407.6 mg/g) and a fast adsorption equilibrium time (0.5 h) for iodide anions. Additionally, the Cu/Al 2 O 3 aerogel could selectively capture iodine anions even in the presence of high concentrations of competing ions (NO 3 - , SO 4 2- , and Cl - at 60 mmol/L). Importantly, the aerogel can operate in a wide pH range of 3–11 without causing secondary pollution. This work demonstrates that low-cost Cu/Al 2 O 3 aerogels exhibit great potential for eliminating radioactive iodine anions.
研究领域:
环境科学
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材料科学
·
水处理
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产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Hao Zhang,Junyan Wang,Minjie Liu,Di Liu
Cu/Al 2 O 3 catalyst was developed by a double hydrolysis precipitation. Over the Cu/Al 2 O 3 catalyst, a continuous mode of N-methylations of nitroarenes with methanol was successfully achieved under the exogenous base- and H 2 - free condition. Methylation process of nitroarenes could be controlled just by adjusting reaction conditions, affording the desired N-monomethylanilines or N, N-dimethylanilines, respectively. The characterization displayed that the double hydrolysis precipitation method made active metal Cu surface enrichment and high dispersion, meanwhile endow Cu/Al 2 O 3 with more developed pore system, which were responsible for the higher performance of our catalyst relative to Cu/Al 2 O 3 -CP. Compared with the reported batch mode, our procedure possessed the merits of low cost, environment-friendliness, better controllability and wide universality.
研究领域:
催化化学
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绿色化学工程
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2025
·
IF 5.3
Qingxiang Zhang,Dengqian Zhang,Zhen Wang,Zheng Liu,Yukun Xi,Wei Zhang,Chen Zhang,Yin Liu
Catalytic transfer hydrodechlorination of plastic pyrolysis oil on supported transition-metal catalysts using isopropanol as a hydrogen donor was investigated in this work. The catalysts were characterized by N2 adsorption, X-ray diffraction, hydrogen temperature-programmed desorption, and X-ray photoelectron spectroscopy, and the reaction products were identified by GC-MS. Among various Al2O3-supported transition-metal (Cu, Co, Ni) catalysts, Cu/Al2O3 exhibited the best catalytic transfer hydrodechlorination performance due to the superior activation ability of Cu/Al2O3 for isopropanol. The doping of Ni in Cu/Al2O3 significantly enhanced its catalytic activity due to the inherent excellent hydrogenation activity of Ni, good metal dispersion, and strong Ni–Cu interaction in Ni–Cu/Al2O3. GC-MS results revealed that chlorobenzene was hydrogenated to benzene and HCl, and isopropanol was dehydrogenated to form acetone, which was subsequently transformed to methyl isobutyl ketone. The reactivities of three representative organochlorine compounds followed the order of chlorobenzene > tetrachloroethane > tetrachloroethylene. Ultradeep dechlorination of real plastic pyrolysis oil was achieved by catalytic transfer hydrodechlorination over the optimal 15Ni-10Cu/Al2O3 catalyst. The chlorine content of real plastic pyrolysis oil was reduced from 61.7 to 0.5 mg/L with a chlorine removal of 99.2% after reaction for 3 h at the reaction temperature of 210 °C.
研究领域:
化学工程
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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
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Xingling Zhao,Xue Zhou,Yupei Xia,Zihan Xu,Mingjun Song,Zihan Wang,Qingjie Guo,Zaiyong Jiang
Catalytic oxidation of carbon monoxide (CO) by Cu/Al 2 O 3 has garnered increasing interest in recent years due to its promising application prospects. Numerous investigations conducted on the Cu/Al 2 O 3 system, but its catalytic performance for CO oxidation is still not as promising as that of precious metal catalysts. Increasing the loading amount of the active Cu on Al 2 O 3 surface is a feasible method for improving its activity. However, with the increase of Cu loading, the agglomeration and enlargement of Cu particles is inevitable, which reduces the active Cu amount. Therefore, the utilization rate of Cu atoms is not high and the catalytic performance often can not further rise. Enhancing active Cu loading amount as high as possible is a prerequisite to further enlarge the activity of Cu/Al 2 O 3 catalyst. Herein, self-synthesized Al 2 O 3 nanofibers (Al 2 O 3 -nf) with high specific surface area and abundant penta-coordinated aluminum (Al V ) are used as the support to maximize the Cu loading amount by chemical vapor deposition (CVD). And commercially available α-Al 2 O 3 is used for comparative experiment. The high specific surface area could make Cu high dispersion on Al 2 O 3 , even at 20 wt% Cu loads, which is beneficial to high concentration load of active Cu. The catalytic activity of Cu/Al 2 O 3 -nf-CVD gradually increases with the increase of Cu loading from 2 wt% to 20 wt%, exhibiting a clear linear correlation with the surface content of Cu 0 on the catalyst. Meanwhile, this result confirms that Cu 0 plays a crucial role in CO oxidation of Cu/Al 2 O 3 . However, commercial α-Al 2 O 3 reaches its highest activity when the Cu load is 5%, and then its activity begins to decrease due to the agglomeration of particles. Moreover, Cu/Al 2 O 3 -nf-CVD also exhibits remarkable thermal stability for CO oxidation. This work highlights a new strategy to synthesis of high Cu loading amount, high activity and thermostable Cu/Al 2 O 3 catalyst for low-temperature oxidation of CO.
研究领域:
催化化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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
·
电子工程
·
健康检测
✓ 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）