Surfaces and Interfaces
·
2021
·
IF 4.837
Zepeng Fang,Dagui Chen,Fengpo Yan,Jiangquan Lv,Yongjing Wang,Xiangfeng Guan
The water monitoring parameter of chemical oxygen demand (COD) is a universal way to assess organic pollution in aqueous systems. Though the ways for the detection of COD have been developed for decades, it is still a challenge to achieve highly sensitive and portable COD detectors. In this work, a new electrode composite of Ni/ZnO/Cu (CE-1) was prepared for the electrochemical tests of COD. The electrode was structural characterized by using scanning electron microscope (SEM), transmission electron microscope (TEM), and X-ray Diffractometer (XRD), which showed that self-supported Cu microflowers were successfully electrodeposited on the ZnO micro-prims that were firstly loaded on the Ni foils. The electrochemical behaviors were investigated with the comparison of CE-1 and the electrode that Cu nanoparticles were directly deposited on the Ni foil (CE-2). It shows that CE-1 possesses much superior electrochemical properties than CE-2, which indicates that the introduction of ZnO micro-rod the electrode can significantly enhance the electrocatalysis property. CE-1 exhibited a linear COD detection range of 2.3603 to 577.8 mg/L as well as an excellent correlation with the classic dichromate method (R 2 = 0.99933). Moreover, low detection limit of 0.6036 mg/L (the signal blank/slope=3) and high sensitivity of 2.403 × 10 −2 mA / (mg • L −1 ) can be simultaneously achieved by using CE-1, which is hard to attain for its counterparts reported in literature. CE-1 also shows good concordance with the classic method for real water sample detections. Consequently, the environmentally friendly CE-1 is supposed as a promising candidate for COD detection electrode.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE CHEMICAL LETTERS
·
2024
·
IF 9.4
Junyi Yu,Yin Cheng,Anhong Cai,Xianfeng Huang,Qingrui Zhang
Herein, the Cu(III) synthesized from copper plating effluent was developed for the first time to evaluate the onsite degradation performance of heavy metal complexes in the wastewater, thus achieving the purpose of “treating waste with waste”. The results indicated that synthetic Cu(III) presented the excellent decomplexation performance for Cu(II)/Ni(II)-organic complexes. The removal efficiency of Cu(II)/Ni(II)-EDTA significantly increased with increasing Cu(III) dosage, and the degradation of Cu(II)/Ni(II)-EDTA by synthetic Cu(III) system displayed highly pH-dependent reactivity. The radical quencher experiments confirmed that Cu(III) direct oxidation were mainly involved in the degradation of Cu(II)-EDTA. Additionally, the continuous decarboxylation process was proven to be the main degradation pathway of Cu(II)-EDTA in Cu(III) system. The coexisting substances (SO 4 2− , Cl − and fulvic acids) showed little impacts at low level for the removal of Cu(II)/Ni(II)-EDTA, while retarded the degradation of Cu(II)-EDTA slightly at high level, which features high selective oxidation. Encouragingly, it was also effective to remove Cu(II)/Ni(II)-EDTA from in treating actual Cu/Ni-containing wastewater through synthetic Cu(III) treatment.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Wei Zhou,Mazhar Ahmed Memon,Mengmeng Niu,Xinqiang Fan,Yanan Jiang,Xian Zhang,Yuan Liu
Copper (Cu) based catalysts are frequently used in CO 2 hydrogenation, particularly in reverse water-gas shift (rWGS) and CO 2 -to-methanol reaction. Cu 0 and Cu + are the key species affecting the catalyst performance and product distribution . Therefore, constructing and adjusting Cu 0 /Cu + active pairs is significant for the catalyst design . In this study, Cu 0 /Cu + active pairs are obtained by utilizing the properties of perovskite-type oxides (PTOs). A series of CaTi 1-x Cu x O 3 and Ca 0.8 La 0.2 Ti 1-x Cu x O 3 (x = 0.05, 0.10, 0.15, 0.30, 0.40 and 0.50) were synthesized via citric acid complexing method and part of the Cu species entered the PTOs lattice. After reduction, large Cu particles and highly-dispersed Cu clusters were obtained simultaneously. The dispersed Cu clusters have more interfaces with the PTOs and provide abundant Cu + while large Cu particles tend to aggregate and supply mainly Cu 0 . Cu 0 activates H 2 and CO 2 and plays a vital role in the rWGS reaction . Cu + is the active site for methanol synthesis and it can strongly absorb CO. The ratio of Cu 0 /Cu + varies with different Cu content and doping La can also adjust the chemical state of surface Cu. The performance test demonstrates that both excessively high and low Cu 0 /Cu + ratios are beneficial for CO generation, while a moderate ratio is suitable for methanol synthesis . These insights provide a method for regulating the chemical state of surface metal species and help the catalyst design for CO 2 hydrogenation.
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
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
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Xinyu Li,Huawang Zhao,Yating Huang,Xiaomin Wu,Zhiwei Huang,Huazhen Shen,Guohua Jing
A composite catalyst was prepared by mechanically mixing Cu-SSZ-13 and MnCeTiO x to improve selective catalytic reduction (SCR) of NO x by ammonia. The optimal mass ratio of Cu-SSZ-13 and MnCeTiO x components in the composite catalysts was 1:1, where the NO x conversion was improved by around 40% in the temperature range of 150–300 °C compared with Cu-SSZ-13 alone. MnCeTiO x presented significantly stronger ability on the activation of NO to nitrates species than Cu-SSZ-13. Infrared (IR) and density functional theory (DFT) results showed that active nitrates intermediate on MnCeTiO x might migrate to Cu-SSZ-13, which assisted the oxidation of single Cu + to Cu 2+ to complete the Cu redox cycle. This avoided the rate-determining step that formation and oxidation of Cu + dimers in low-temperature SCR over Cu-SSZ-13. The research results are beneficial to the rational design of SCR catalysts with high-performance at low temperatures.
研究领域:
催化化学
·
环境科学
✓ 已验证
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
JOURNAL OF CATALYSIS
·
2022
·
IF 8.047
Jiancai Hou,Jiangliang Hu,Liping Chang,Jiancheng Wang,Zequan Zeng,Dongxia Wu,Xinmin Cui,Weiren Bao,Junxuan Yao
Cu-Ce mixed oxides with different Cu contents were synthesized through a sol–gel method, after which their effect on benzene combustion catalysis was evaluated. CeCu0.50 calcined at 300 °C (CeCu0.50–300) exhibited a high areal rate [2.0 × 10 −6 mol/(m 2 h)] and turnover frequency (0.16 s −1 ) at 170 °C, thus demonstrating the strong synergistic effect between CuO and CeO 2 . The catalyst durability and influence of H 2 O(g) on catalytic activity were also investigated. Correlation analyses between the catalytic activities and the amount of copper species, indicated that CuO x clusters and the Cu-[O x ]-Ce structure were the main active sites and bridge for oxygen transfer, respectively. Furthermore, benzene did not adsorb onto the copper species. The effect of temperatures on surface oxygen vacancies and oxygenated intermediates were also evaluated. Taken together, our findings provided key insights into the synergistic effects of different copper species on benzene combustion.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2020
·Vol. 49
·期 3
·2159-2163
·
IF 1.774
Wang Yan,Wang Yishu,Ma Limin,Han Jing,Guo Fu
Because of its tetragonal structure, β -Sn exhibits anisotropy in electromigration behavior. The diffusivity of Cu atoms along the c -axis of Sn is much faster than that along the a -axis; therefore, the orientation of the c -axis exerts a strong influence on Cu atomic motion. In this work, the effect of Sn grain c -axis on Cu atomic motion was investigated by using Cu reinforced Sn3.5Ag composite solder joints. The microstructure and morphology of the solder joints were characterized by scanning electron microscopy (SEM) equipped with a backscattered electron (BSE) detector. It was found that intermetallic compounds (IMCs) in the solder matrix were formed due to the migration of Cu atoms to the surface of the solder joint under current stressing. There was a large amount of IMCs on the solder matrix which protruded from the solder matrix. By changing the direction of electron flow, i.e. changing the anode and the cathode side, the IMCs which formed after current stressing in the solder matrix disappeared and the protruding Sn remained unchanged. The results revealed that the growth of IMCs was closely related to the migration of Cu atoms, while Cu atomic motion depended on the orientation of the Sn grain c -axis.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2018
·Vol. 11
·期 3
·1123-1130
·
IF 4.674
Xiao-Li Li,Guo-Hui Yang,Meng Zhang,Xiao-Feng Gao,Hong-Juan Xie,Yun-Xing Bai,Ying-Quan Wu,Jun-Xuan Pan,Yi-Sheng Tan
Graphical Tuning selectivity : Cu/SiO 2 was prepared by ammonia evaporation and used as catalyst for the direct synthesis of ethanol from CO hydrogenation. Both the Cu + /(Cu + +Cu 0 ) values and copper crystallite sizes had significant effects on the selectivity towards ethanol. Cu/SiO 2 catalyst was prepared by the ammonia evaporation method for the direct synthesis of ethanol from CO hydrogenation. The catalyst exhibited the initial ethanol selectivity as high as 40.0 wt %, which dramatically decreased from 40.0 to 9.6 wt % on the stream of 50 h. XRD, XPS, TEM and N 2 O titration techniques were employed to elucidate the ethanol selectivity change and catalyst structure evolution during reaction process. The experiment and characterization results indicated that both Cu + /(Cu + +Cu 0 ) value and copper crystallite size had great effects on the ethanol selectivity. During the initial 38 h, the ethanol selectivity obviously decreased from 40.0 to 18.2 wt %, and Cu + /(Cu + +Cu 0 ) value on the catalyst surface rapidly dropped from 0.67 to 0.39, while the copper crystallite size remained almost unchanged. However, during the reaction period of 38–50 h, the Cu + /(Cu + +Cu 0 ) value possessed no distinct change, but a further decrease in ethanol selectivity and a rapid aggregation in Cu particles were observed simultaneously. The present systematic investigation demonstrated that the decrease of Cu + /(Cu + +Cu 0 ) value was the main factor for the loss of ethanol selectivity during the initial 38 h, whereas the rapid growth of Cu particles during the reaction period of 38–50 h were mainly contributed to the further decline of ethanol selectivity.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Ting Wang,Fuli Sun,Shoujie Liu,Guilin Zhuang,Benxia Li
Supported Cu single-atom (Cu-SA) catalysts have exhibited unique activity and selectivity in CO 2 reduction, but they generally suffer from the easy transformation of active Cu δ+ into inactive Cu 0 . Herein, porous TiO 2 supported Cu single atoms (Cu-SAs/TiO 2 ) photocatalyst was fabricated and dioxygen (O 2 ) enhanced photocatalytic CO 2 reduction performance of Cu-SAs/TiO 2 was investigated by in-situ characterizations and theoretical calculations. The results showed that both activity and stability of Cu-SAs/TiO 2 photocatalyst could be improved by feeding a small amount of O 2 (117.6 ppm) in the reaction system. The competitive electron transfer to O 2 on Cu-SAs/TiO 2 maintained dynamic stability of Cu δ+ active sites, and O 2 -derived *OOH species lowered the formation energy barrier of key intermediate *COOH as well as delivered *H species for accelerating intermediates protonation process. Total yield rate of CH 4 and CO reached 34.64 μmol·g cat ·h −1 for CO 2 photoreduction over Cu-SAs/TiO 2 after introducing 117.6 ppm O 2 , accompanied by enhanced durability.
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
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Yan-Ping Yu,Meng-Meng Pan,Ming Jiang,Xu Yu,Li Xu
Despite the rapid development of metal-organic framework materials (MOFs), the development of multifunctional MOFs and their application in catalytic and antibacterial fields is still of great significance. In this work, a three-dimensional flower-like Cu-MOF was successfully synthesized by a simple solvothermal method and its pyrolytic derivative Cu-N-C 450 was obtained through pyrolysis of the Cu-MOF. For the first time, the Cu-MOF was preliminarily verified to have laccase-like activity and exhibited excellent antibacterial ability to Escherichia coli ( E. coli ) at a very low concentration of 10 µg/mL without the addition of other substrate. Interestingly, we found the re-assembly of the micro-sized Cu-MOF to generate larger sized flower-like structures which was not common in the self-assembled phenomenon. We found the collision and centrifugation induced external force interaction might be the main factor. In addition, the Cu-MOF was also be used as adsorbent to remove environmental pollutants, such as methylene blue , and the Cu-N-C 450 can rapidly catalyze the degradation of methylene blue with a high efficiency to 96.7%. This work offers a multifunctional MOFs material and promotes the exploration of extending application of the MOFs.
研究领域:
材料科学
·
催化化学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 15
·2579
·
IF 5.719
Beiying Qi,Xinchang Wang,Xinyue Wang,Jipeng Cheng,Yuanyuan Shang
Metal–organic framework (MOF)-derived pure ZnO and Cu-doped ZnO nanocages were fabricated by calcining a zeolitic imidazole framework (ZIF-8) and Cu-doped ZIF-8. The morphology and crystal structure of the samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). It was found that Cu doping did not change the crystal structures and morphologies of MOF-derived ZnO nanocages. The H2S-sensing properties of the sensors based on ZnO and Cu-doped ZnO nanocages were investigated. The results indicated that the H2S-sensing properties of MOF-derived ZnO nanocages were effectively improved by Cu doping, and the optimal doping content was 3 at%. Moreover, 3 at% Cu-doped ZnO nanocages showed the highest response of 4733 for 5 ppm H2S at 200 °C, and the detection limit could be as low as 20 ppb. The gas-sensing mechanism was also discussed.Keywords:MOF-derived ZnO;nanocages;Cu doping;H2S sensing
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）