INTERNATIONAL JOURNAL OF MODERN PHYSICS B
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2017
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IF 0.736
Hongcheng Peng,Weihong Qi,Wenhai Ji,Siqi Li,Jieting He
Combining the bond-energy model and Debye theory, we generalized the Gibbs free energy model for Cu–Pt nanoparticles (NPs) by introducing a shape factor considering the shape effect. We studied the structural stability of the Cu–Pt NPs and plotted the corresponding composition-, shape- and size-dependent phase diagrams. It is shown that the Cu–Pt NPs can form alloyed structure in a large size range. But when the particle size continues to decrease, the NPs will form the core–shell structure due to surface segregation. Meanwhile, the composition segregation could make the atoms of less-content element to gather in the surface. The predictions from the present calculated phase diagrams are consistent with a series of experimental results in literatures. To further prove the efficiency of the phase diagrams, we synthesized the alloyed Cu–Pt NPs of 4–15 nm by a co-reduction method, which is in agreement with the predictions from the phase diagrams.
研究领域:
材料科学
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纳米技术
✓ 已验证
DOI
高影响因子
VACUUM
·
2024
·
IF 3.8
Xiu Wen,Zhixiu Yang,Lijing Gao,Ruiping Wei,Xiaomei Pan,Jin Zhang,Guomin Xiao
Electrocatalytic reduction of CO 2 affords a potential way to mitigate the greenhouse effect and fuel crisis. In this work, we compared highly-dispersed CuO nanocomposites and Cu–Cu 2 O nanocomposites which all derived from Cu x Al-LDH for CO 2 electrochemical reduction . The Cu–Cu 2 O based nanocomposites obtained through the restoration strategies still retain its layered structure, simultaneously increasing dual Cu–Cu 2 O active sites, which exhibit excellent performance in selective reduction of CO 2 to C 2 H 4 . The Cu 5 Al-ER obtained through in-situ electrochemical reduction is modified by bulk phase, which can regulate active species, increase surface active sites, enhance C–C coupling. Meanwhile, the electrochemical strategy offers numerous benefits, including gentle conditions, adjustable monitoring, exceptional efficiency and adaptability. We have confirmed that cost-effective Cu–Cu 2 O based nanocomposite derived from Cu 5 Al-LDH can effectively promote C–C coupling during electrochemical CO 2 conversion and improve FE C2H4 . The FE C2H4 of Cu 5 Al-ER reaches 36% at −1.2 V vs. RHE. And the current density reaches −172 mA·cm −2 at −1.6 V vs. RHE. The results showed that compared to Cu 5 Al-LDO, the FE C2H4 of Cu 5 Al-ER increased by 2.6 times. In addition, Cu 5 Al-ER exhibits excellent stability during the 12 hours CO 2 catalytic reduction process.
研究领域:
化学
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环境科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2024
·
IF 3.4
Yu Sun,Jinxing Mi,Liang Li,Shuxiu Yu,Shixiong Yuan,Guimin Wang,Jianjun Chen,Junhua Li
The unique ability of Cu + to enhance C-C coupling makes it important in the field of CO 2 reduction reaction (CO 2 RR) over Cu-based catalyst, while Cu + is very prone to deactivation. Hereby, we propose a simple and feasible stabilization strategy to stabilize Cu + species through reducing Cu-Mg-Al hydrotalcite by adding ascorbic acid, which owns stable product selectivity in a span of 6 h at −0.95 V vs.RHE. Characterization results show that the excellent stability is promoted by the heterostructure of Cu 2 O and hydrotalcite with retained Cu + species, which derives from Cu 2 O and slow down the rapid reduction of Cu + to Cu 0 .
研究领域:
材料科学
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电化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2024
·
IF 2.8
Ye Liu,Lei Zhang,Yubo Kuang,Xiaoqian Xiang,Haohan Tao,Guangran Di,Xiaojing Yin,Meicheng Li,Xiao-Jun Lv
The photocatalytic CO 2 reduction has the problems of low selectivity of single product. Here, the preparation of Cu modified tubular C 3 N 4 (CTN) was studied. The increase of the active site inhibits the recombination of electrons (e-) and holes (h + ) and improves the selectivity of CO 2 reduction products. Finally, the CO and CH 4 yields of 1.5 % CTN photocatalyst are 11.55 μmol·g −1 and 4.72 μmol·g −1 , respectively, which are 5 times higher than that of tubular C 3 N 4 photocatalyst. The selectivity of 2 % CTN to CH 4 is up to 68 %, indicating that the prepared CTN photocatalyst has high CO 2 reduction activity and CH 4 selectivity.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2018
·
IF 4.521
Shaozhong Li,Yu Wang,Bin Yang,Limin Guo
Mesostructured catalysts with optimized microstructure and surface properties endowed them attractive catalytic performance. Herein, the mesostructured AlCeO supports with different weight ratio of Al 2 O 3 and CeO 2 have been prepared on the basis of a self-assembly sol-gel process, then 15 wt.% Cu was loaded onto the mesostructured AlCeO supports by incipient wetness impregnation method. The mesostructured AlCeO supports with varied ratio of Al 2 O 3 to CeO 2 resulted in the very different Cu particle size, and for the optimized catalyst Cu/AlCeO-7 (the amount of Al 2 O 3 in AlCeO support was 70 wt.%), the Cu crystal size was around 7 nm based on the characterization of XRD and TEM. The Cu/AlCeO-7 catalyst had strong metal-support interactions (SMSI) and more Cu-ceria interface, which was confirmed by the XPS. Furthermore, the Cu/AlCeO-7 catalyst showed the highest exposed Cu surface area ( S Cu ) (25.5 m 2 /g cat ) from the analysis results of H 2 -TPR and dissociative chemisorption of nitrous oxide. The CO 2 -TPD results demonstrated the Cu/AlCeO-7 had strong surface basicity. Hence, Cu/AlCeO-7 catalyst showed the highest space time yield of methanol (STY MeOH ). The CO 2 conversion (Cu/AlCeO-7, V(H 2 )/V(CO 2 ) = 3/1, GHSV = 6000 mL h −1 g −1 and P = 4 MPa) was up to 22.5% at 553 K, the methanol selectivity can reach 94% at 473 K, and the STY MeOH was up to 7.2 mmol g cat. -1 h -1 at 493 K. The as-prepared mesostructured Cu/AlCeO-7 exhibited a promising catalyst candidate for CO 2 hydrogenation to methanol.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Yufang Wu,Zhenqiang Lv,Xin Zhou,Junjie Peng,Yuning Tang,Zhong Li
We report a bifunctional SBU-tuning strategy that simultaneously enhances the selective CO 2 adsorption capacity of Cu-BTC and its structural stability under moisture. A series of Gly@Cu-BTCs were prepared by grafting glycine (Gly) to the secondary building units (SBUs) of the commercially available Cu-BTC through the nano-seed assistant ultrafast room temperature synthesis. N 2 isotherms evidenced higher BET specific surface area and pore volume of Gly@Cu-BTCs than that of Cu-BTC. Hence, Gly 0.3 @Cu-BTC exhibited a superior CO 2 capacity of 5.4 mmol/g at ambient conditions, which is 12% higher than that of Cu-BTC. Besides, the adsorptive selectivity of Gly 0.3 @Cu-BTC for the equimolar CO 2 /CH 4 and CO 2 /N 2 mixtures was separately up to 8.53 and 59.38, being 11% and 15% higher compared to that of Cu-BTC. More importantly, the stability of Gly 0.3 @Cu-BTC against moisture was improved. After 10 days’ exposure in 55% relative humidity, Gly 0.3 @Cu-BTC preserved 80% of its original CO 2 capacity, while only 9% CO 2 capacity remained for Cu-BTC. In addition, negligible CO 2 capacity loss of Gly 0.3 @Cu-BTC was observed in the subsequent 10 days in moisture after the initial exposure. Gly 0.3 @Cu-BTC exhibited excellent regenerability, and its CO 2 desorption efficiency reached up to 98% based on the consecutive adsorption-desorption cycles. The origination of the improved stability under moist of Gly 0.3 @Cu-BTC was interpreted with DFT calculation. The bifunctional SBU-tuning strategy demonstrated in this work enables the potential adsorptive separation application of Cu-BTC under moist working condition.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
RARE METALS
·
2021
·Vol. 41
·期 3
·931-941
·
IF 4.003
Guo Jun,Wang Zi-Yuan,Zhu Yu-Ke,Chen Lin,Feng Jing,Ge Zhen-Hua
Bi 2 S 3 is composed of inexpensive and environmental friendliness elements, which has received extensive interests and been investigated as a promising mid-temperature thermoelectric material for years. Even pure Bi 2 S 3 possesses a high Seebeck coefficient and low thermal conductivity, its low electrical conductivity leads to a low figure of merit (ZT) value. In this work, Bi 2 S 3 fabricated by solid-state melting combined with spark plasma sintering can significantly enhance the thermoelectric performance via introducing small amounts of Cu and BiCl 3 . Cu interstitial doping and Cl substitution on S site result in a large increase in electrical conductivity. Additionally, the enhanced phonon scattering is derived from the point defects caused by element doping, the grain boundaries, and the small amount of secondary phase, which leads to the low thermal conductivity. Finally, a high ZT value of 0.7 is obtained at 773 K and reaches a large average ZT of 0.36 in the temperature range from room temperature (RT) to 773 K for the Cu-interstitial-doped and BiCl 3 -alloyed (Cu 0.01 Bi 2 S 3 + 0.175 mol% BiCl 3 ) sample. Furthermore, the mechanical properties of the Cu 0.01 Bi 2 S 3 + 0.175 mol% BiCl 3 sample are lower than those of other Bi 2 S 3 samples, which stem from the weak chemical bonding strength. Graphic abstract
研究领域:
材料科学
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能源材料
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热电材料
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2025
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IF 4.1
Hong Qian,Binxia Yuan,Yuhao Liu,Li Wang,Rui Zhu,Pengyu Dong
TiO 2 has low photocatalytic activity due to its easy recombination of photogenerated charges and low visible light utilization efficiency. This study utilized the keto-enol tautomerism principle of fructose in an alkaline environment to successfully obtain Cu 2 O/TiO 2 (CT), Cu 2 O/TiO 2 /Cu (CTC), and TiO 2 /Cu (TC) catalysts. As Cu(I) transformed into Cu(0), the bandgap narrowed, significantly enhancing visible light absorption. Photocatalytic tests showed that CT-0.15 exhibited the highest hydrogen production rate (279.53 μmol g −1 h −1 ), which was 25.18 times higher than that of TC-2. However, CTC-1 had the highest CO production rate (10.58 μmol g −1 h −1 ). Optoelectronic test revealed that CT-0.15 and CTC-1 had higher separation efficiency of photogenerated exciton. Density functional theory (DFT) calculations indicated that the change in the valence state of Cu influenced the reaction mechanism, with CT being favorable for the adsorption of H + in HER and CTC promoting the adsorption of CO 2 in carbon dioxide reduction reaction (CO2RR).
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2019
·Vol. 9
·期 6
·538
·
IF 3.444
Lili Liu,Xiaojing Zhou,Li Liu,Shuai Jiang,Yingjie Li,Luxia Guo,Shijuan Yan,Xishi Tai
Three bimetallic Cu–Ni nanoparticle-supported catalysts were synthesized by co-immobilization followed by H2reduction. A chromium(III) terephthalate metal organic framework (MIL-101), titanium dioxide (TiO2), and carbon (C) with different properties (acidity and Brunauer–Emmett–Teller surface area) were selected as supports for studying the effect of the support nature on the catalytic activity and selectivity in the oxidation of benzyl alcohol. The physicochemical properties of the Cu–Ni-supported catalysts were characterized by XRD, NH3-TPD, nitrogen adsorption/desorption, TEM, EDS, XPS, and ICP-OES. Bimetallic Cu–Ni nanoparticles were highly dispersed on the support. The catalytic activities of CuNi/MIL-101, CuNi/TiO2, and CuNi/C were tested in the selective oxidation of benzyl alcohol to benzaldehyde in the presence of molecular oxygen under mild reaction conditions. The highest benzaldehyde yields were achieved with CuNi/TiO2, CuNi/MIL-101, and CuNi/C catalysts at 100 °C within 4 h under 5, 3, and 3 bar of O2, respectively. The bimetallic Cu–Ni-supported catalysts possessed two types of catalytic active sites: acid sites and bimetallic Cu–Ni nanoparticles. The CuNi/MIL-101 catalyst possessed a high number of acid sites and exhibited high yield during selective benzyl alcohol oxidation to benzaldehyde. Importantly, the catalysts exhibited a high functional group (electron-donating and electron-withdrawing groups) tolerance. Cu–Ni-supported catalysts with an Cu:Ni mole ratio of 1:1 exhibited the highest yield of 47% for the selective oxidation of benzyl alcohol to benzaldehyde. Reusability and leaching experiment results exhibited that CuNi/MIL-101 showed better stability than CuNi/TiO2and CuNi/C catalysts due to the large porous cavities of MIL-101 support; these cavities can be used to trap bimetallic Cu–Ni nanoparticles and inhibit nanoparticle leaching.Keywords:Cu–Ni nanoparticles;MIL-101;TiO2;carbon;benzyl alcohol oxidation
研究领域:
催化
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
·
2021
·Vol. 2021
·期 35
·3601-3610
·
IF 2.524
Shaozhong Li,Qing Guo,Jin Li,Yongke Hu,Jiayu Lin
Graphical The mesostructured Cu/AlZnO-9 catalyst with 15 wt % Cu was prepared for the hydrogenation of CO 2 to methanol. The well mesostructure increased the exposed Cu surface area and CO 2 adsorption sites, which accelerated the CO 2 conversion, and the ZnO in catalyst increased the generation of methanol. In addition, the well mesostructure heightened the stability of supported Cu catalyst due to the high dispersion of Cu nanoparticles. In this work, the mesostructured Cu/AlZnO catalysts were prepared for the CO 2 hydrogenation to methanol. Experimental results showed that the weight ratio of Al 2 O 3 and ZnO affected the morphology of the mesoporous AlZnO supports and surface properties of the mesostructured Cu/AlZnO catalysts. The AlZnO-9 (the Al 2 O 3 mass within the AlZnO support was 90 wt%) with loose spongy porous structure and high surface area facilitated the Cu nanoparticle dispersion. Thus, the Cu/AlZnO-9 catalyst showed higher exposed Cu surface area ( S Cu ) and more exposed CO 2 adsorption sites, which accelerated the CO 2 conversion. Meanwhile, the ZnO added into catalysts increased the strength of surface basicity and the surface concentration of Zn species, which promoted the catalytic activity of CO 2 hydrogenation to methanol. In addition, the well mesostructure heightened the stability of supported Cu catalyst due to the high dispersion of Cu nanoparticles.
研究领域:
化学工程
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催化材料
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环境科学
✓ 已验证
DOI
高影响因子
Journal of Advanced Ceramics
·
2022
·Vol. 11
·期 3
·427-442
·
IF 11.534
Zhang Yu,Han Shuai,Wang Mingyuan,Liu Siwei,Liu Guiwu,Meng Xianfeng,Xu Ziwei,Wang Mingsong,Qiao Guanjun
One-dimensional nanofibers can be transformed into hollow structures with larger specific surface area, which contributes to the enhancement of gas adsorption. We firstly fabricated Cu-doped In 2 O 3 (Cu-In 2 O 3 ) hollow nanofibers by electrospinning and calcination for detecting H 2 S. The experimental results show that the Cu doping concentration besides the operating temperature, gas concentration, and relative humidity can greatly affect the H 2 S sensing performance of the In 2 O 3 -based sensors. In particular, the responses of 6%Cu-In 2 O 3 hollow nanofibers are 350.7 and 4201.5 to 50 and 100 ppm H 2 S at 250 °C, which are over 20 and 140 times higher than those of pristine In 2 O 3 hollow nanofibers, respectively. Moreover, the corresponding sensor exhibits excellent selectivity and good reproducibility towards H 2 S, and the response of 6%Cu-In 2 O 3 is still 1.5 to 1 ppm H 2 S. Finally, the gas sensing mechanism of Cu-In2O3 hollow nanofibers is thoroughly discussed, along with the assistance of first-principles calculations. Both the formation of hollow structure and Cu doping contribute to provide more active sites, and meanwhile a little CuO can form p–n heterojunctions with In 2 O 3 and react with H 2 S, resulting in significant improvement of gas sensing performance. The Cu-In 2 O 3 hollow nanofibers can be tailored for practical application to selectively detect H 2 S at lower concentrations.
研究领域:
材料科学
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纳米技术
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化学
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2025
·Vol. 155
·期 6
·1-14
·
IF 2.4
Yang Ke,Zhou Bo,Dong Kun,Wu Yan,Huang Qu,Lv Jingbo,Wan Ziyi,Yang Mingzhu
With the acceleration of industrialization and urbanization, the treatment of organic pollutants in water bodies has become a global problem. Photocatalytic technology is regarded as an ideal solution due to its green and efficient characteristics. However, traditional powder catalysts have the problem of difficult recovery. Using copper foam as the substrate to load photocatalysts is a feasible solution. Cu/CuO/Cu 2 O with a core–shell structure was prepared by a simple solvothermal method based on copper foam. Under visible light irradiation, the Cu/CuO/Cu 2 O catalyst has a high catalytic efficiency for Congo red (95% within 180 min) and a significant adsorption and degradation ability for tetracycline hydrochloride. The results of the density functional theory calculation and electrochemical tests reveal that a Schottky heterojunction forms between Cu 2 O and CuO, the band gap of Cu 2 O is 0.57 eV, and the free energy of Cu/CuO/Cu 2 O is 0.24 eV, close to 0 eV, revealing the ternary composite’s possibility to evolve hydrogen. The heterojunction generated by Cu 2 O and CuO improves the material’s charge transport efficiency. Furthermore, this ternary composite based on copper foam easy to recycle and reuse, and can maintain nearly 90% degradation efficiency after 8 cycles. This concept offers a method for planning and building interfaces in nanocomposite structures. Graphical
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）