FUEL
·
2020
·
IF 5.578
Bowen Lu,Zewu Zhang,Xiaoshan Li,Cong Luo,Yongqing Xu,Liqi Zhang
Cu catalysts have been widely used in CO 2 utilization due to their low reduction temperature and excellent CO 2 hydrogenation performance. It is important to well design Cu catalyst with high efficiency and durability for CO 2 hydrogenation. In this work, CuCe(rod) catalysts with various Cu contents were prepared. The physicochemical properties of the CuCe(rod) catalysts were described by XRD, TEM, N 2 -physisorption and H 2 -TPR.The effect of Cu content on catalytic performance of CO 2 hydrogenation with CuCe(rod) catalysts was also studied. Results showed that a high Cu content enhanced CO 2 conversion. The 40CuCe(rod) catalyst exhibited the best CO 2 conversion performance. At the reaction temperature of 400 °C, the CO production rate (CO 2 conversion) and CO selectivity based on the 40CuCe(rod) catalyst could reach 1.69 mol/g cat /h (41.1%) and nearly 100%, respectively. The analysis of kinetic measurements revealed that the activation energy of the 40CuCe(rod) catalyst was lower than that of other catalysts with different Cu contents during a reverse water–gas shift reaction. The lower activation energy and the interface structure of Cu-O x -Ce were closely related to CO 2 hydrogenation activity and remarkable stability for 96 h with minimal loss of CO 2 conversion activities.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Xinran Ji,Tengqian Chen,Chang Shen,Ye Zhao,Ke Zhou,Meiling Sun,Yinghua Yu,Lining Fan,Hui Zheng,Qiong Wu,Qiangyuan Zhang,Yang Zhang
Nickel-copper-zinc (NiCuZn) ferrites with high permeability and low magnetic loss have high application potential in high-frequency electronics. In this work, NiCuZn ferrite samples with different Cu contents were prepared by a two-step sintering method. First, the optimal temperatures of the two-step sintering method (1025/925 °C) were confirmed, thereafter the influence of the Cu content on the crystal structure, microstructure, magnetic and dielectric properties of NiCuZn ferrite were studied in detail. Structural characterization showed that an increase in Cu content promoted grain growth and resulted in NiCuZn ferrites with a denser microstructure and decreased porosity. However, a second phase of CuO formed once the content of Cu (x value) reached 0.16. The magnetic hysteresis loops revealed that the saturation magnetization increased as x increased and the highest value of 57.3 emu/g was obtained at x = 0.14. The dielectric property measurement showed that increasing the Cu content could improve the dielectric constant and reduce the dielectric loss. The permeability measurements showed an increase in permeability with Cu content from x = 0.10 to x = 0.14 and a decrease when x = 0.16. Consequently, a NiCuZn ferrite with an appropriate microstructure and with high permeability (μ'=855), low magnetic loss (tanδ μ = 0.02), and high saturation magnetization (57.3 emu/g) could be obtained at a Cu content of x = 0.14 and sintering temperatures of 1025/925 °C in the two-step sintering method. This NiCuZn ferrite provides new guidance for developing RF frequency multilayer inductors.
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
ACS Applied Nano Materials
·
2021
·
IF 5.097
Jilei Chen,Lu Zhang,Shulan Li,Feng-Lei Jiang,Peng Jiang,Yi Liu
Copper indium selenide (CISe) quantum dots (QDs) are a class of extremely appealing candidates for various biological applications due to their composition- and size-dependent photoluminescence and low toxicity. However, the synthesis of high-quality water-soluble CISe QDs with controlled composition in the aqueous phase is still a great challenge, which limits their biological applications. Moreover, the effects of the copper content in CISe QDs on the fluorescence and the corresponding mechanism are still subject to debate. Herein, a composition-tunable aqueous synthesis of high-quality Cu-deficient CISe QDs was presented, and the effects of the copper content on the fluorescence of CISe QDs was studied by the time-resolved fluorescence. The composition of CISe QDs could be flexibly controlled by manipulating the reaction temperature, the reaction time, and the Cu/In precursor ratio. The time-resolved fluorescence of CISe QDs with different Cu/In ratios suggested that the donor–acceptor pair (DAP) recombination was enhanced gradually with the increase of copper vacancies, resulting in the enhancement of fluorescence. However, if copper vacancies achieved an excessive concentration, the fluorescence would decrease possibly due to Auger recombination. The optimized CISe QDs with the maximum quantum yield of 10.3% were obtained with the Cu/In ratio, reaction temperature, and reaction time of 1/5, 170 °C, and 1 h, respectively. Based on the intense emission of the Cu-deficient CISe QDs, a highly sensitive “turn-on” fluorescent probe was developed for the detection of adenosine triphosphate (ATP) in living cells with a limit of detection of 56 nM. This work provides a paradigm for the aqueous-phase synthesis and applications of ternary I–III–VI QDs.
研究领域:
生物化学
·
纳米医学
·
分析化学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 12
·期 1
·127
·
IF 5.076
Qining Wang,Quanwang Yan,Yu Zhao,Jie Ren,Ning Ai
Cu-Mg-Al layered double hydroxides (LDHs) with amine modification were prepared by an organic combination of an anionic surfactant-mediated method and an ultrasonic spalling method usingN-aminoethyl-γ-aminopropyltrimethoxysilane as a grafting agent. The materials were characterized by elemental analysis, XRD, SEM, FTIR, TGA, and XPS. The effects of the Cu2+content on the surface morphology and the CO2adsorption of Cu-Mg-Al LDHs were investigated, and the kinetics of the CO2adsorption and the photocatalytic reduction of CO2were further analyzed. The results indicated that the amine-modified method and appropriate Cu2+contents can improve the surface morphology, the increase amine loading and the free-amino functional groups of the materials, which were beneficial to CO2capture and adsorption. The CO2adsorption capacity of Cu-Mg-Al N was 1.82 mmol·g−1at 30 °C and a 0.1 MPa pure CO2atmosphere. The kinetic model confirmed that CO2adsorption was governed by both the physical and chemical adsorption, which could be enhanced with the increase of the Cu2+content. The chemical adsorption was suppressed, when the Cu2+content was too high. Cu-Mg-Al N can photocatalytically reduce CO2to methanol with Cu2+as an active site, which can significantly improve the CO2adsorption and photocatalytic conversion.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2017
·Vol. 33
·期 8
·1672-1680
·
IF 0.767
LIAO Pei-Yi,ZHANG Chen,ZHANG Li-Jun,YANG Yan-Zhang,ZHONG Liang-Shu,GUO Xiao-Ya,WANG Hui,SUN Yu-Han
A series of Cu/Co/Mn/Al catalysts derived from hydrotalcite precursors with different Cu/Co molar ratios (0, 0.1, 0.5, 1.0, and 2.0) were prepared and used for the synthesis of higher alcohols from syngas. N2 physical adsorption desorption, inductively coupled plasma atomic
emission spectrometry (ICP-AES), X-ray diffraction (XRD), scanning electron microscopy (SEM), hydrogen temperature-programmed reduction (H2-TPR), thermogravimetry (TG), and high-resolution transmission electron microscopy (HRTEM) techniques were employed to investigate the physical
and chemical properties of the Cu/Co/Mn/Al catalysts. The results show that the optimum Cu content can increase specific surface area, improve reducibility, and form regular layered structure to provide more uniform distribution of active sites, thereby enhancing catalytic activity and alcohol
selectivity. When the Cu/Co molar ratio was 0.5, the yield of alcohol and the alcohol selectivity reached the maximum values of 0.071 g·g-1·h-1 and 35.9%, respectively.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Qizhi Dong,Wenxia Zeng,Hansheng Wan,Shumin Yu,Cancheng Guo,Meiling Huang
A highly efficient and CO tolerant PdCu electrocatalysts supported on amino-rich, cationic poly(diallyl dimethyl ammonium chloride)(PDDA) functionalized TiO 2 (PdCu/TiO 2 (P)-C) has been developed. The catalysts were characterized by transmission electron microscopy (TEM),X-ray diffraction (XRD)，cyclic voltammograms and chronoamperometry. The PtCu particles with average size ∼3.5 nm are well dispersed on TiO 2 (P). PdCu/TiO 2 (P)-C catalysts exhibit a superior electrocatalytic activity and stability for the formic acid oxidation reaction compared with the Pd/TiO 2 (P)-C. Electrochemical measurements indicate that PdCu/TiO 2 (P)-C(1:2) catalyst has the best performance for formic acid electro-catalytic oxidation in terms of durability and Pd-mass activity among three catalysts (Pd 1 Cu 1 ,Pd 1 Cu 2 ,Pd 1 Cu 3 ). The possible reason is that the addition of Cu is beneficial to lower appropriately the d-band center of Pd and increase the electrochemical active surface area of the PdCu/TiO 2 (P)-C nanocatalysts, but when the content of Cu rises to a certain extent, the morphology of the catalyst nanoparticles will transform into linear structure leading to increased particle size.
研究领域:
化学工程
·
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2025
·
IF 4.5
Yuwen Pan,Guoning Ji,Boyao Zhang,Xin Li,Yongqi Tian,Shuangshuang Zhang,Depeng Zhao,Rongda Zhao,Fufa Wu,Lihua Miao
Electrocatalytic technology serves as a critical pathway for clean energy conversion, where high-entropy alloys demonstrate outstanding catalytic performance owing to their unique multi-principal-element design. This work systematically investigates Cu x (CoCrNiFe) 100-x HEAs as cost-effective bifunctional catalysts for both freshwater and seawater electrolysis. The optimized Cu 50 (CoCrNiFe) alloy exhibits excellent catalytic activity with low overpotentials of 248.3 mV for HER and 327 mV for OER at -10 mA cm -2 in alkaline freshwater, along with remarkable stability (<5% decay after 24 hours). Notably, in alkaline seawater electrolyte, it achieves even better HER performance (234 mV) while maintaining comparable OER activity, and demonstrates exceptional 50-hour durability in overall water splitting tests. These findings not only provide new insights into HEA-based catalyst design but also highlight the great potential of such materials for practical large-scale hydrogen production from seawater resources, representing a significant step toward sustainable energy solutions.
研究领域:
材料科学
·
电化学
·
能源材料
·
催化化学
·
可持续能源
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2021
·
IF 6.057
Rongrong Wang,Yong Cao,Hao Qu,Yanbo Wang,Lei Zheng
Copper sulfate is a widely used agent to control insects, bacteria and algae for fishery. However, excess amount of copper ions in water accumulate in aquatic products through the ecological cycle system, highly threatening food safety and public health. Therefore, it is urgent to develop a rapid and efficient method for the determination of copper content in aquatic products. In this study, we developed a label-free biosensor for Cu(II) based on a graphene field-effect transistor gated by structure-switching aptamer probes (SSA-GFET) against Cu(II) we obtained before. The detection mechanism of the biosensor is attributed to the surface charge shift and the potential change of the gate electrode upon the specific binding of Cu(II). The SSA-GFET biosensor has a low detection limit of 10 nM and a linear range of 10 nM to 3 μM to Cu(II). In addition to the excellent selectivity to Cu(II), the biosensor also showes the advantage of high recovery rate for detection of Cu(II) in real fish samples. Because of the detection characteristics of label-free SSA-GFET, it has great advantages in the field of food safety and environmental detection.
研究领域:
分析化学
·
环境科学
·
食品安全
✓ 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）