Science China-Technological Sciences
·
2015
·Vol. 58
·期 5
·881-888
·
IF 1.192
Yang AiLing,Li ShunPin,Wang YuJin,Wang LeLe,Bao XiChang,Yang RenQiang
Ag@Cu 2 O core-shell metal-semiconductor nanoparticles (NPs) were prepared by using solution phase strategy. It was found that Ag@Cu 2 O core-shell NPs were easily converted to Ag@Cu bimetallic core-shell NPs with the help of surfactant PVP and excessive reducer ascorbic acid in air at room temperature, which is a unique phenomenon. Varying volumes of Ag colloidal solutions were added into the reaction mixtures containing fixed initial concentrations of Cu 2+ and PVP, Ag@Cu 2 O and Ag@Cu core-shell NPs with fixed core size but varying outer shell thicknesses could be obtained. The composites, structures, morphologies and extinction properties of Ag@Cu 2 O and Ag@Cu core-shell NPs were systematically characterized by XRD, TEM and extinction spectra. Both of these NPs show wide tunable optical properties. The extinction peaks could be shifted from 421 nm to 700 nm. FTIR results reveal that Cu + ions on the surface of Cu 2 O nanocrystalline coordinate with N and O atoms in PVP and further are reduced to metallic Cu by excessive ascorbic acid and then form a nucleation site on the surface of Cu 2 O nanocrystalline. PVP binds onto a different site to proceed with the reduction until all the Cu sources in Cu 2 O NPs are completely assumed. And the shell of Cu 2 O is converted to Cu shell. The synthesis approach in this paper is simple and also a promising reference for synthesizing other core-shell NPs. Ag@Cu 2 O NPs can be easily converted to Ag@Cu NPs in air at room temperature, which is promising to be used in electronic devices.
研究领域:
纳米材料化学
·
无机功能材料
·
胶体与界面化学
·
光谱学
·
半导体物理
✓ 已验证
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2019
·
IF 3.25
Yuting Chu,Muhammad Asim Khan,Fengyun Wang,Mingzhu Xia,Wu Lei,Sidi Zhu
Arg-Mt, was fabricated by modifying sodium montmorillonite (Na-Mt) with Arginine monohydrochloride (Arg salt), to adsorb Pb(II) and Cu(II) in aqueous solution. The X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectrum, thermal analysis (TG/DTG), Brunauer-Emmett-Teller (BET) and Scanning electron microscope (SEM) were employed to investigate the properties of Na-Mt and Arg-Mt. The effects of the amount of modifier, pH value, the initial concentration of M(II), temperature and contact time were tested in a single adsorption system. The isotherm model was well matched with the Langmuir curve and the kinetic adsorption fitted well with the pseudo-second-order rate equation. The saturated adsorption of Pb(II) and Cu(II) by Arg-Mt were 124.69 and 29.15 mg/g, respectively, which were higher than that of Na-Mt (89.08 and 23.93 mg/g). The thermodynamic equation indicated that the adsorption process was spontaneous, endothermic, and the randomness of the samples changed a little after adsorption. The adsorption capacity of heavy metal ions in the binary co-adsorption system was poor than single adsorption system. Furthermore, the adsorbed M(II) onto Arg-Mt can hardly be dissolved under weak acidic condition (pH > 4) according to the desorption experiments. High-efficiency and low-cost make Arg-Mt to be used in the removal of heavy ions in aqueous solution.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 33
·80817-80827
·
IF 5.8
Huang Guofu,Wang Mianmian,Sun Xinying,Liu Haijian,Liu Fangfang
In this work, pomegranate peel extracts were used as the green reducing agent to synthesize Cu/Fe nanoparticles (P-Cu/Fe nanoparticles) and removed tetrabromobisphenol A (TBBPA) in aqueous solution. P-Cu/Fe nanoparticles were amorphous and irregularly spherical. The surfaces of nanoparticles contained Fe 0 , Fe 3+ oxides (hydroxides), and Cu 0 . The bioactive molecules from pomegranate peel were extremely important for the synthesis of nanoparticles. P-Cu/Fe nanoparticles had excellent removal performance for TBBPA, and 98.6% of TBBPA (5 mg L −1 ) was removed within 60 min. The removal reaction of TBBPA by P-Cu/Fe nanoparticles was well-fitted with the pseudo-first-order kinetic model. The Cu loading was critical for TBBPA removal with an optimum value of 1.0 wt%. A weakly acidic condition (pH 5) was more favorable for the removal of TBBPA. The removal efficiency of TBBPA increased with the rise of temperature and decreased with increasing initial TBBPA concentration. The activation energy ( E a ) was 54.09 kJ mol −1 , indicating that the removal of TBBPA by P-Cu/Fe nanoparticles was mainly surface-controlled. Reductive degradation was the main mechanism of TBBPA removal by P-Cu/Fe nanoparticles. In conclusion, green synthesized P-Cu/Fe nanoparticles using pomegranate peel waste show great potential for the remediation of TBBPA in aqueous solution.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Youqin Lu,Min Wang,Cunguang Yuan,Jinsheng Zhao,Jianfeng Yu
Cyclic voltammetry (CV) was used to fabricate carbon supported Pt-Cu alloy (Pt-Cu/C) for oxygen reduction reaction (ORR) at ambient temperature. A flowerlike structure of Pt-Cu nanoparticles were analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy was used to confirm the surface chemical composition and metallic state. And, electrochemical measurements such as CV, rotating disk electrode, rotating ring-disk and electrochemical impedance spectroscopy were applied to obtain the kinetic constants and the reaction mechanisms of the ORR. Compared with Pt/C, Cu/C, Pt-Cu/C exhibits the highest efficient catalytic activity for ORR, as evidenced by the highest current densities of the polarization curves, lowest onset oxidation potential and charge transfer impedance. The average electron transfer number and hydrogen peroxide calculated from RRDE are about 3.87 and 6.71%, respectively. These results show that the synthesized Pt-Cu/C has excellent electrocatalytic activity and the ORR is a four-electron dominant reduction pathway.
研究领域:
电化学
·
纳米材料科学
·
催化化学
·
能源材料
·
电分析化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 16
·13384-13391
·
IF 3.289
Bin Lu,Renzong Hu,Jiangwen Liu,Jun Liu,Hui Wang,Min Zhu
To improve the coulombic efficiency (CE) and cycle life of SnO2 anode in lithium ion batteries, SnO2–Cu–graphite composites with dual scale embedding structure are synthesized by ball milling. The SnO2–Cu composite, in which SnO2 nanoparticles with grain size less than 10 nm are uniformly dispersed in inactive nanocrystalline Cu matrix, is firstly obtained by milling the mixture of SnO2 and Cu nanopowders (molar ratio 1 : 2), and then further milling with graphite (C) to obtain SnO2–Cu–C composite with microsized graphite sheets as matrix of SnO2–Cu composite. The 50 h-milled SnO2–Cu composite exhibits higher initial CE (76.0 ± 1.5%) and subsequent CE than 50 h-milled SnO2. Furthermore, the SnO2–Cu–C composite anode is capable of retaining a maximum charge capacity of 450.8 mA h g−1 at 100 mA g−1 after 80 cycles with a capacity retention ratio of 74.4%, displaying superior cyclic stability to as-milled SnO2, SnO2–Cu and SnO2–C composites. The improved CE and cycleability are attributed to the unique dual scale embedding structure that offers good conductivity of electron and lithium ion as well as the nanostructure stability of active materials. This unique composite structure might be extended to other high-capacity anode materials, to achieve high performance lithium ion batteries.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
锂离子电池
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2024
·Vol. 59
·期 9
·3930-3946
·
IF 3.5
Miao Xin,Wang Liying,Shi Yunxin,Chen Guohua,Liu Yunfei,Wu Gaoqi,Cao Zhenzhu,Zhang Yongfeng
Microsphere 3D structure of Cu/Mn 3 O 4 @SC composite was fabricated by pyrolyzing the bimetallic CuMn-MOF, which was composed of Cu 2+ , Mn 2+ and sulfur-containing ligand 2,5-thiophene dicarboxylic acid (H 2 TDC). The composite of Cu/Mn 3 O 4 @SC is used as a high-performance anode material for the lithium-ion batteries cycle exhibiting stable capacities of 715 mAh g −1 after 100 cycles at 200 mA g −1 and outstanding long cycle performance with a reversible capacity of 508 mAh g −1 at 0.5 A g −1 after 500 cycles. The superior performance for the Cu/Mn 3 O 4 @SC anode is mainly attributed to the mutual supporting characteristics of heterojunction synergistic effect, thus avoiding damage in the process of energy storage process. In addition, the kinetic analysis based on CV reveals that the transport kinetics mechanism of the Cu/Mn 3 O 4 @SC is synergistically controlled by the surface capacitive and pseudocapacitive behaviors. The EIS proves that the introduction of Cu enhances the conductivity of the material and the rate of lithium-ion diffusion. Graphical abstract Cu- and S-doped multielement microspheres was fabricated by pyrolyzing CuMn-MOF supported by 2, 5-thiophene dicarboxylic acid.
研究领域:
材料科学
·
电化学
·
纳米技术
·
能源存储
·
无机化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Yijie Han,Cheng Chen,Yuxin Li,Lixiang Zhou,Yeqing Lan,Ying Li
Cu-Y binary oxysulfide was synthesized for the first time. A series of batch experiments were conducted to determine the optimum conditions for preparing the adsorbent and further investigate the effects of the initial pH and coexisting anions on the removal of arsenic. The results indicate that the adsorbent displays an extremely excellent performance in removing both As(III) and As(V). The maximal adsorption capacities at the initial pH 6.0 are 263.16 and 270.27 mg/g for As(III) and As(V), respectively. The adsorbent remains relatively stable even at the initial pH 3 and at this pH it also exhibits a very high removal efficiency for As(V). Based on Fourier-transform infrared (FTIR) spectrometer and X-ray photoelectron spectrometer (XPS) analyses and other results obtained in our experiments, a possible mechanism for the removal of arsenic is proposed. The dissolved O 2 is activated to O 2 − via a single-electron transfer reaction from Cu(I) on the adsorbent, which oxidizes As(III) to As(V). Then, arsenate anions are adsorbed onto the surface of the adsorbent and the adsorbed arsenate anions further react with the hydroxyl groups on the surface of the adsorbent via an ion exchange or precipitate with Y(III) on the surface of the adsorbent .
研究领域:
环境科学
·
化学
·
水处理
✓ 已验证
DOI
高影响因子
Carbon Letters
·
2024
·Vol. 34
·期 2
·603-609
·
IF 5.5
Mai Xuan-Dung,Bui Thi-Thu,Tran Dai-Luat,Mai Van-Tuan,Duong Ngoc-Huyen,Nguyen Van-Hao
Composites of carbon quantum dots (CQDs) are important materials to utilize the optical properties of CQDs in diverse applications including photoluminescence-based sensing and LED phosphors. Combining pre-prepared CQDs with a polymeric matrix usually causes changes in the optical properties of CQDs due to unavoidable aggregation. Recently, the preparation of composites based on in-situ formed CQDs has been debated to overcome the aggregation limits of the conventional mixing methods. Herein, we have demonstrated the synthesis of homogeneous CQDs composites by simple thermal annealing blends of aluminum hydroxide (AlOH), citric acid (CA), and urea (URA). Transmission electron microscopy (TEM), X-ray diffraction, and Raman spectroscopy studies revealed the formation of individual CQDs with a diameter of about 2–9 nm dispersed homogeneously over the AlOH matrix. The composites have a broad excitation band centered at about 360 nm and exhibit excitation-dependent photoluminescence which was similar to that of hydrothermally synthesized CQDs from CA and URA. The photoluminescent intensity of the composite was stable to UV irradiation and responded selectively to Cu(II) ion demonstrating its potential application in Cu(II) sensing.
研究领域:
材料科学
·
纳米技术
·
分析化学
·
光学传感
✓ 已验证
DOI
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 42
·15889-15896
·
IF 8.307
Yuxiang Ma,Yumin Zhang,Yiwen Ma,Tianping Lv,Bin Xiao,Xinya Kuang,Xiyu Deng,Jin Zhang,Jianhong Zhao,Qingju Liu
Single atom catalysts (SACs) have an extremely high atom utilization and distinctive structures and properties in the field of photocatalysis. However, the premise of conducting scientific research and applications is still the stability and catalytic activity of single atoms on suitable substrates. Metal organic frameworks (MOFs), as one of the most suitable single-atom substrates, have tunable internal structures, unsaturated coordination bonds, and high specific surface areas. In this work, Ti-based MOF, MIL-125, was adopted as the precursor to prepare mesoporous Cu-loaded TiO2. During the synthesis of MIL-125, a Cu source was added, and Cu atoms were fixed by partly replacing Ti atoms in the Ti–O octahedron to coordinate with O atoms, resulting in a good dispersity, good stability and high loading amount. Experimental investigations demonstrated that dispersed Cu single atoms act as reaction centres, besides being able to accelerate the transfer of photoelectrons. Under simulated sunlight, the H2 evolution rate of the optimum Cu–TiO2 sample reaches 17.77 mmol g−1 h−1, nearly 101 times higher than that of the pure mesoporous TiO2. The apparent quantum efficiency (AQE) is 20.15% under 365 nm irradiation. This research opens a new thinking to preparing high stability and high activity single atom photocatalysts.
研究领域:
材料科学
·
光催化
·
能源科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Yixi Sun,Jiabin Zhou,Dan Liu,Xi Li,Hong Liang
It is important to develop a catalyst that can maintain good activity in alkaline environment for Fenton or Fenton-like reactions. In order to achieve stable Fenton catalytic degradation in a wide pH range, this study reports Cu-doped MnFe 2 O 4 heterogeneous catalysts still has excellent effect when the pH is extended to 11 for removing organic pollutants, such as tetracycline hydrochloride (TC-HCl). The synergistic effect among Fe, Mn and Cu ions has been proved to enhanced the catalytic activity in this work. When the molar ratio of Cu/Mn = 4:1, the porous Cu 0·8 Mn 0·2 Fe 2 O 4 materials had the highest photo-Fenton catalytic activity compared with pure MnFe 2 O 4 , CuFe 2 O 4 and other Cu x Mn 1-x Fe 2 O 4 . The XPS showed that Cu 0·8 Mn 0·2 Fe 2 O 4 formed oxygen vacancies, which exposed more active sites to attract more H 2 O 2 for TC-HCl degradation. Results indicated 94.3% of TC-HCl was efficiently degraded by 0.1 g/L Cu 0·8 Mn 0·2 Fe 2 O 4 with 50 mM H 2 O 2 at pH = 11 under 30 min visible light irradiation, and the corresponding apparent rate constant was 0.08286 min −1 . With free radicals quenching experiment, O 2 − was responsible for the high catalytic degradation and OH was participated in the photo-Fenton reaction. To sum up, Cu 0·8 Mn 0·2 Fe 2 O 4 exhibited high activity, great stability and easily recyclable, which eliminated the pH limitation of the Fenton reaction and provided practical application performance for water purification .
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2019
·
IF 7.279
Baosong Li,Tianyong Mei,Dandan Li,Shengsong Du
Ni-Cu/TiN nanocomposites were electrodeposited by incorporation of TiN nanoparticles in Ni-Cu matrix from sulphate-citrate bath with additives. Ultrasonic assistance was performed in an external ultrasonic bath at ultrasonic frequency of 40 KHz and acoustic power of 300 W. The effects of current density on surface morphology, structural and electrochemical properties of Ni-Cu/TiN nanocomposites were examined. Results indicated that the presence of TiN changes the texture of nickel coating. Corrosion resistance of the composite deposit was enhanced by ultrasonic-assisted electrodeposition. The average roughness value ( R a ) of Ni-Cu/TiN is 26–34 nm, which is rougher than Ni-Cu alloy ( R a = 4–5 nm). Not only the ultrasonic agitation, but also the current density affects the corrosion properties of the products. Ni-Cu/TiN nanocomposite electrodeposited at 5 A dm −2 has the highest corrosion resistance.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2019
·Vol. 150
·期 3
·815-825
·
IF 2.372
Huang Yan-Feng,Zhang Lu,Ma Li,Li Ying,Zhong Chongli
Abstract Fe 3 O 4 @Cu/C and Fe 3 O 4 @CuO composites were achieved using nanoparticle-encapsulated MOFs Fe 3 O 4 @HKUST-1 as both a precursor and a self-sacrificing template. Fe 3 O 4 @HKUST-1 was thermally converted into magnetic Fe 3 O 4 @Cu/C and Fe 3 O 4 @CuO composites in different atmosphere (N 2 and air). The resulting composites not only kept superparamagnetic characteristics, but also exhibited improved peroxidase-like catalytic activity and high stability when compared to the precursor Fe 3 O 4 @HKUST-1. The morphology, crystal structure, magnetic and porous properties of Fe 3 O 4 @Cu/C and Fe 3 O 4 @CuO composites were characterized, and the kinetics parameters and the influence factors on the peroxidase-mimicking activity such as temperature, pH and H 2 O 2 concentration were evaluated. On account of the excellent peroxidase-like activity, the as-prepared Fe 3 O 4 @Cu/C and Fe 3 O 4 @CuO composites were successfully used for the catalytic removal of methylene blue (MB) dye with H 2 O 2 oxidant. This work provides an effective way to fabricate highly reactive MOFs-derived biomimetic catalysts, which have potential applications in bioassays and pollutant degradation. Graphic Abstract Fe 3 O 4 @Cu/C and Fe 3 O 4 @CuO composites were achieved using Fe 3 O 4 nanoparticle-encapsulated HKUST-1 as self-sacrificial templates and demonstrated excellent peroxidase-like activity.
研究领域:
材料科学
·
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）