SOLAR ENERGY
·
2018
·
IF 4.374
Lianjing Zhao,Leilei Zhao,Weinan Xue,Wenjuan Fang,Yuan Wang,Yan Li
To improve the catalytic activity of carbons in counter electrodes (CEs), Cu nanoparticles (NPs) were introduced into mesoporous N-doped carbons (N-C) derived from metal-organic frameworks (MOFs) to prepare the composites of N-C and Cu NPs (N-C@Cu) via impregnation and subsequent reduction method in this work. The obtained N-C@Cu composites with 2–4 nm Cu NPs uniformly distributing in N-C were deposited onto fluorine doped tin oxide (FTO) substrates by screen-printing to fabricate CEs in quantum dot solar cells (QDSCs). The N-C@Cu CEs exhibit higher electrocatalytic activity than both pristine N-C/FTO and commonly used Cu 2 S/FTO CEs, which could be ascribed to the synergistic effect between Cu x S NPs with the excellent electrocatalytic ability and MOF derived N-C with high graphitization, large hydrophilic surface as well as the abundant dopant active sites on the reduction of polysulfide. The superior performance of N-C@Cu composites results in an improved fill factor and a high short circuit current density. Based on optimized N-C@Cu CEs and Zn-Cu-In-Se quantum dot sensitizers, the QDSCs obtained present a promising power conversion efficiency of 9.23%, significantly superior to those of pristine N-C/FTO (7.20%) and Cu 2 S/FTO (8.89%) CEs based QDSCs.
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DOI
高影响因子
Surface Topography-Metrology and Properties
·
2020
·Vol. 8
·期 3
·035014
·
IF 1.613
Weiwei Zhang,Cuicui Ji,Qiang Fu,Zhongquan Shi
In this work, the structure and properties of ZrO2 nanoparticle reinforced Ni–W, Ni–B and Ni–Cu matrix nanocomposite coatings were comparatively studied. Their surface morphology, composition, microstructure, topography, hardness, wear and corrosion resistance were examined by various methods . The nanocomposites exhibit dense, nodular-like morphology with nanocrystalline structure. The results show that the ZrO2 particles have homogeneously dispersed in the nanocomposites. The formation of the protrusion structure was partly attributed to the heterogeneous distribution of the electric field. The presence of ZrO2 nanoparticles could refine the crystallite size of the Ni–W, Ni–B and Ni–Cu alloy matrix to 12.5 ± 1, 10.5 ± 0.5 and 15 ± 0.1 nm, respectively. The corrosion resistance of these nanocomposites can be improved by the incorporation of ZrO2 nanoparticles into the alloy matrix. The Ra of Ni–W/ZrO2, Ni–B/ZrO2 and Ni–Cu/ZrO2 nanocomposites are about 53 ± 3, 69 ± 2, 18 ± 1 nm, respectively, expressing the rougher surface of Ni–B/ZrO2 compared to the others. It indicated that the composition of these alloy matrix have different crystallite size, which could affect the surface roughness of the electrodeposits. The inclusion of ZrO2 particles in Ni-based alloys could enhance its properties. The reinforcement effect of the anti-wear properties of the nanocomposites was proposed. The Rct value of the Ni–W–ZrO2, Ni–B–ZrO2, Ni–Cu–ZrO2 were 50.93, 105.18, 44.67 kΩ · cm2, respectively, indicating that the Ni–B–ZrO2 nanocomposite coating has the highest corrosion resistance. The Rct values depends on not only the composition of the coatings, but also the electrodeposition conditions, which influence the crystallize size and compactness of the electrodeposits. The order of the microhardness and anti-wear properties is Ni–W–ZrO2 > Ni–B–ZrO2 > Ni–Cu–ZrO2.
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DOI
高影响因子
Journal of Superconductivity and Novel Magnetism
·
2020
·Vol. 33
·期 11
·3607-3613
·
IF 1.244
Zhang Zhanjun
In this work, we reported the Ce-Cu co-substituted M-type strontium hexaferrites Sr 0.7 Ce 0.3 Fe 12- x Cu x O 19 (0.00 ≤ x ≤ 0.50) prepared by using the solid-state method. The specific effect of Ce-Cu co-substitution on the magnetoplumbite structure and magnetic properties were studied systematically. The canonical M-type strontium hexagonal phase has been formed for our prepared sample in all doping range, which also has been confirmed by FTIR spectrum. In all compositional range, by the way, the magnetic competition of ferromagnetism-antiferromagnetism is reduced and gradually disappeared under the increasing substitution. Likewise, an obvious improvement of magnetic properties can be obtained; that is, H c increases from 2850 to 3800 Oe and the value of M s can reach up to 70.305 emu/g. The intrinsic stability and superior magnetic performance of such kind of material indicate a promising potential candidate in multilayer inductors.
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Qixia Dong,Haoran Dong,Yangju Li,Junyang Xiao,Shuxue Xiang,Xiuzhen Hou,Dongdong Chu
In this work, zero-valent Fe-Cu bimetallic nanoparticles were synthesized using a facile method, and applied to activate sulfite for the degradation of sulfamethazine (SMT) from the aqueous solution. The key factors influencing SMT degradation were investigated, namely the theoretical loading of Cu, Fe-Cu catalyst dosage, sulfite concentration and initial solution pH. The experimental results showed that the Fe-Cu/sulfite system exhibited a much better performance in SMT degradation than the bare Fe 0 /sulfite system. The mechanism and possible degradation pathway of SMT in Fe-Cu/sulfite system were revealed. The reactive radicals that played a dominant role in the SMT degradation process were •OH and SO 4 •- , while the loading of Cu induced the synergistic effect between Fe and Cu. The redox cycle between Cu(I)/Cu(II) remarkably contributed to the conversion of Fe(III) to Fe(II), greatly enhancing the catalytic performance of Fe-Cu bimetal. In real groundwater applications, the Fe-Cu/sulfite system also exhibited satisfactory SMT degradation. The 30-day aging tests of Fe-Cu particles demonstrated that the aging of catalyst was not obviously affecting the removal of SMT. Furthermore, the reusability of catalyst was evidenced by the recycling experiments. This study provides a promising application of bimetal activated sulfite for enhanced contaminant degradation in groundwater.
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DOI
高影响因子
CATALYSIS LETTERS
·
2020
·Vol. 150
·期 12
·3394-3401
·
IF 2.482
Qiao Chenxia,Jia Wenlan,Zhong Qiming,Liu Bingyu,Zhang Yifu,Meng Changgong,Tian Fuping
Abstract Novel Cu-nanoparticles (NPs) embedded in porous carbon materials (Cu@C-x) were prepared by one-pot pyrolysis of metal–organic frameworks (MOF) HKUST-1 at different temperatures. The obtained material Cu@C-x was used as a cost-effective catalyst for the hydrogenation of nitrobenzene using NaBH 4 as the reducing agent under mild reaction conditions. By considering the catalyst preparation and the catalytic activity, a pyrolysis temperature of 400 °C was finally chosen to synthesize the optimal catalyst. When the aromatic nitro compounds with reducible groups, such as cyano, halogen, and alkyl groups, were tested in this catalytic hydrogenation, an excellent selectivity approaching 100% was achieved. In the recycling experiment, a significant decrease in nitrobenzene conversion was observed in the third cycle, mainly due to the very small amount of catalyst employed in the reaction. Hence, the easily prepared and cost-effective Cu@C-400 catalyst fabricated in this study demonstrates potential for the applications in selective reduction of aromatic nitro compounds. Graphic Abstract The catalyst Cu@C-400 exhibited 100 % conversion and high selectivity for the hydrogenation of industrially relevant nitroarenes.
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高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 5
·1097
·
IF 5.076
Luran Zhang,Xinchen Du,Hongjie Lu,Dandan Gao,Huan Liu,Qilong Lin,Yongze Cao,Jiyang Xie,Wanbiao Hu
L10ordered FePt and FePtCu nanoparticles (NPs) with a good dispersion were successfully fabricated by a simple, green, one-step solid-phase reduction method. Fe (acac)3, Pt (acac)2, and CuO as the precursors were dispersed in NaCl and annealed at different temperatures with an H2-containing atmosphere. As the annealing temperature increased, the chemical order parameter (S), average particle size (D), coercivity (Hc), and saturation magnetization (Ms) of FePt and FePtCu NPs increased and the size distribution range of the particles became wider. The ordered degree,D,Hc, andMsof FePt NPs were greatly improved by adding 5% Cu. The highestS,D,Hc, andMswere obtained when FePtCu NPs annealed at 750 °C, which were 0.91, 4.87 nm, 12,200 Oe, and 23.38 emu/g, respectively. The structure and magnetic properties of FePt and FePtCu NPs at different annealing temperatures were investigated and the formation mechanism of FePt and FePtCu NPs were discussed in detail.
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DOI
高影响因子
Journal of Energy Chemistry
·
2021
·
IF 9.676
Ziyi Li,Haigang Hao,Jingjing Lu,Chengming Wu,Rui Gao,Jifan Li,Chun-Ling Liu,Wen-Sheng Dong
Here we exquisitely fabricated Cu/ZrO 2 -dp catalysts with plentiful Cu-ZrO 2 interfaces by depositing amorphous ZrO 2 onto Cu nanoparticles for the hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL). With the created plentiful Cu-ZrO 2 interfaces, the optimal catalyst 3Cu/ZrO 2 -dp exhibited exceptional catalytic performance under mild reaction conditions, and achieved the highest GVL mass productivity of 266.0 mmol GVL·h −1 ·g −1 Cu, which was 12.5 and 2.3 times of Cu/ZrO 2 catalysts with equivalent Cu loadings prepared by traditional impregnation (3Cu/ZrO 2 -im) or co-precipitation (3Cu/ZrO 2 -cp). As far as we know, this GVL mass productivity stood at the highest level compared with those obtained using non-noble metal catalysts under similar reaction conditions. By systematic investigation with multiple characterizations, density functional theory (DFT) calculations, and kinetic studies, it was found that interfacial active centers were created at Cu-ZrO 2 interfaces, which contained oxygen vacancies (O v ), negatively charged Cu δ− and partially reduced Zr 3+ . The O v favored the adsorption and activation of LA via its ketone group, while negatively charged Cu δ− was able to enhance heterolysis of H 2 , which resulted in the formation of H + -Cu δ− and Zr 3+ -H − active species via hydrogen spillover. Also, plentiful acid sites, which derived from coordinatively unsaturated and defective Zr species, generated at Cu-ZrO 2 interfaces. With the cooperation of interfacial active centers (Cu δ− -O v -Zr 3+ ) and acid sites, the fabricated 3Cu/ZrO 2 -dp with plentiful Cu-ZrO 2 interfaces achieved excellent catalytic performance for the hydrogenation of LA to GVL. Hence, the synergistic catalysis of Cu-ZrO 2 interfaces provided an effective strategy for designing catalysts with a satisfactory performance for the hydrogenation of LA, which also can be expanded to other hydrodeoxygenation reactions.
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高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Tingting Yu,Lei Tao,Zhiyi Liu,Xuge Zhang,Tao Gan,Wensheng Yan,Lirong Zheng,Ge Meng,Wei Chen,Shoujie Liu,Chenliang Ye,Jian Zhang
Unique active sites make single-atom (SA) catalysts promising to overcome obstacles in homogeneous catalysis but challenging due to their fixed coordination environment. Click chemistry is restricted by the low activity of more available Cu(II) catalysts without reducing agents. Herein, we develop efficient, O-coordinated SA Cu(II) directly catalyzed click chemistry. As revealed by theoretical calculations of the superior coordination structure to promote the click reaction, an organic molecule-assisted strategy is applied to prepare the corresponding SA Cu catalysts with respective O and N coordination. Although they both belong to Cu(II) centers, the O-coordinated one exhibits a 5-fold higher activity than the other and even much better activity than traditional homogeneous and heterogeneous Cu(II) catalysts. Control experiments further proved that the O-coordinated SA Cu(II) catalyst tends to be reduced by alkyne into Cu acetylide rather than the N-coordinated catalyst and thus facilitates click chemistry.
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DOI
高影响因子
APPLIED CLAY SCIENCE
·
2017
·
IF 3.101
Fabien Habimana,Da Shi,Shengfu Ji
This paper highlights the synthesis of Cu-BTC supported on Montmorillonite (Mt) to form Cu-BTC/Mt composite materials and examines their important role in adsorptive desulfurization process of fuel liquids . Cu-BTC/Mt composites were synthesized by solvothermal synthesis using varying Cu-BTC content (30%, 40% and 50%) and a well-known and constant amount of montmorillonite was used as support. The synthesized composites were then characterized using XRD , FT-IR, TEM and BET techniques. The adsorptive desulfurization performance of the as-prepared composite materials was investigated and their ability to remove thiophene from thiophene/ n -octane model oil was studied under mild operating conditions namely: temperature near room temperature, atmospheric pressure and at different model oil/adsorbent mass ratio. Investigation results have shown that the 40%Cu-BTC/Mt composite sample has the best desulfurization performance for thiophene removal. After 6 h of desulfurization, under the reaction conditions of temperature of 30 °C and at a model oil/adsorbent mass ratio of 100:1, the percentage of sulfur removal was 76% while the adsorption desulfurization capacity reached 28.95 mgS/gMOF. The 40%Cu-BTC/Mt composite sample could be reused for at least five consecutive rounds. The adsorption kinetics fit well both the pseudo-first order rate equation and pseudo-second order rate equation models.
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高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Yan Liu,Yamin Zheng,Panpan Dong,Wenzhuang Zhang,Wenjie Wu,Junjie Mao
Development of high-performance heterogeneous catalytic materials is important for the rapid upgrade of chemicals, which remains a challenge. Here, the benzene oxidation reaction was used to demonstrate the effectiveness of the atomic interface strategy to improve catalytic performance. The developed B,N-cocoordinated Cu single atoms anchored on carbon nanosheets (Cu1/B–N) with the Cu–N2B1 atomic interface was prepared by the pyrolysis of a precoordinated Cu precursor. Benefiting from the unique atomic Cu–N2B1 interfacial structure, the designed Cu1/B–N exhibited considerable activity in the oxidation of benzene, which was much higher than Cu1/N–C, Cu NPs/N–C, and N–C catalysts. A theoretical study showed that the enhanced catalytic performance resulted from the optimized adsorption of intermediates, which originated from the manipulation of the electronic structure of Cu single atoms induced by B atom coordination in the Cu–N2B1 atomic interface. This study provides an innovative approach for the rational design of high-performance heterogeneous catalytic materials at the atomic level.
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高影响因子
AICHE JOURNAL
·
2019
·Vol. 66
·期 1
·e16746
·
IF 3.463
Chao Bian,Yin-Ning Zhou,Zheng-Hong Luo
Controlled radical polymerization (CRP) under external field has been an attractive research area in these years. In this work, a new electron transfer mechanism, that is, sonochemically induced electron transfer (SET) was introduced to mediate polymerization for the first time. The activator Cu I X/L complex was (re)generated from Cu II X 2 /L in dimethylsulfoxide (DMSO) by the SET process in the presence of free ligand tris(2-dimethylaminoethyl)amine (Me 6 TREN). The investigation of polymerization including the mechanistic insights and effect of experimental conditions on the rate of reaction has been undertaken. Kinetics of Cu(II)-catalyzed CRPs via SET under different conditions (i.e., Me 6 TREN concentration, catalyst loading, targeted degree of polymerization, and sonication power) were conducted in an unprecedentedly controlled manner, yielding polymers with predetermined molar masses and low dispersities ( Đ < 1.12). Attractively, the polymerization can be performed without the piezoelectric nanoparticles and exogenous reducing agent. Contamination by nonliving chains formed from sonochemically generated radicals is avoided as well. All of these results supported that Cu(II)-based catalyst activation enabled by ultrasonication has a promising potential in scale-up of CRP.
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高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Yanzhu Ye,Ying Liu,Zhongshui Li,Xiaohuan Zou,Hui Wu,Shen Lin
The Cu-In 2 O 3 /C nanocomposite was prepared by a simple solid-phase reduction method. The introduction of In 2 O 3 into Cu/C to form the Cu-In 2 O 3 /C nanocomposite evidently enhances the electrocatalytic activity for the selective reduction of CO 2 to CO. Specifically, the Cu-In 2 O 3 /C nanocomposite exhibits higher Faraday efficiency ( FE = 86.7%) at −0.48 V vs. the reversible hydrogen electrode (RHE) in the electrocatalytic reduction of CO 2 to CO and larger current densities (55 mA cm −2 ) under a low overpotential (−1.08 V vs. RHE). These indicate its superior performance over many of the reported Cu-based catalysts [1] , [2] , [3] , [4] . It was also found that by rationally adjusting the applied potential, tunable syngas can be formed, which can be used to synthesize formic acid, methyl ether, methanol, synthetic fuels, or other bulk chemicals through appropriate industrial processes. Furthermore, the Cu-In 2 O 3 /C nanocomposite maintains good stability in the electrocatalytic reduction of CO 2 . This work demonstrates a novel strategy to convert CO 2 into desired products with high energy efficiency and large current density under low overpotential by the rational designing of non-precious metal catalysts.
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高影响因子
危险品化学品经营许可证（带存储）