Nanomaterials
·
2018
·Vol. 8
·期 11
·900
·
IF 3.504
Longshi Rao,Yong Tang,Hanguang Lu,Shudong Yu,Xinrui Ding,Ke Xu,Zongtao Li,Jin Z. Zhang
We developed a microreactor with porous copper fibers for synthesizing nitrogen-doped carbon dots (N-CDs) with a high stability and photoluminescence (PL) quantum yield (QY). By optimizing synthesis conditions, including the reaction temperature, flow rate, ethylenediamine dosage, and porosity of copper fibers, the N-CDs with a high PL QY of 73% were achieved. The PL QY of N-CDs was two times higher with copper fibers than without. The interrelations between the copper fibers with different porosities and the N-CDs were investigated using X-ray photoelectron spectroscopy (XPS) and Fourier Transform infrared spectroscopy (FTIR). The results demonstrate that the elemental contents and surface functional groups of N-CDs are significantly influenced by the porosity of copper fibers. The N-CDs can be used to effectively and selectively detect Hg2+ions with a good linear response in the 0~50 μM Hg2+ions concentration range, and the lowest limit of detection (LOD) is 2.54 nM, suggesting that the N-CDs have great potential for applications in the fields of environmental and hazard detection. Further studies reveal that the differentdorbital energy levels of Hg2+compared to those of other metal ions can affect the efficiency of electron transfer and thereby result in their different response in fluorescence quenching towards N-CDs.Keywords:microreactor;carbon dots;porous copper fibers;Hg2+detection
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER COMPOSITES
·
2024
·
IF 4.8
Pei Wang,Kai Li,Mingkun Xu,Chaoyong Deng,Lihong Su,Yonggang Guo
To achieve new current collector (pantograph strip, electric brush) with easy industrialization and high strength-toughness, carbon fiber and copper fiber reinforced phenol-formaldehyde (Cu f /C f /PF) composite is fabricated by over-lapping and hot-pressing processes. Cu f /C f /PF composite has compact structure and good interfacial bonding between fibers and resin matrix. Cu f /C f /PF composite is superior to carbon skateboard in terms of electrical conductivity, mechanical strength, and friction behavior. As the carbon fiber content increases, fracture failure mechanism of Cu f /C f /PF composite transforms from plastic failure into brittle fracture. Wear mechanism is studied by combining electrical contacting and sliding friction, and appropriate arc discharge (2.48%) is benefit for the resin-based composite to form a smooth tribolayer, but high arc discharge rate (4.83%) rapidly deteriorates wear condition on the worn surface. Highlights Carbon fiber and copper fiber mixing reinforce resin-based composite. Cu f /C f /PF composite has high strength-toughness and low friction. Fracture failure mode changes to brittle fracture with increasing carbon fiber. Wear mechanism includes electrical contacting and sliding friction. Appropriate arc discharge improve friction performance of resin-based composite.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Geng Zhong,Jiabin Ma,Nanrui Li,Rui Yin,Tianqi Jia,Kangning Cai,Feiyu Kang,Yidan Cao
The anode-free Li metal batteries (AFLMBs), by pairing Li-containing cathode with bare anode current collector (CC), have the potential to enable the maximum improvement (>70 %) in energy density of lithium batteries . Here, we report an ultralight, dual-conductive all-fiber based Cu–CNF-CNT as anode CC, which takes advantage of the high electronic conductivity of carbon nanotube (CNT), good ionic conductivity of copper-coordinated cellulose nanofiber (Cu–CNF), and the three-dimensional porous structure by nanofibers. The interactions between CNTs and Cu-CNFs enables good mechanical strength (4.71 MPa), high electrical conductivity (31.7 S/cm), low density (1.1 g/cm 3 ) and good wettability with electrolyte. The 3D microstructure effectively homogenizes the Li + flux and buffers the volume changes during cycling, leading to stable Li plating/stripping. As a result, AFLMB using Cu–CNF-CNT exhibits improved capacity retention by 33 % compared to that using Cu CC. The significantly elevated energy-density shows great application potential of the Cu–CNF-CNT in AFLMBs.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Ziyang Chang,Shuo Zheng,Shouyi Han,Xueren Qian,Xiaohong Chen,Haiping Wang,Dingqiang Liang,Daliang Guo,Yanguang Chen,Huifang Zhao,Lizheng Sha
Along with the developing of flexible electronics, there is a strong interest in high performance flexible energy storage materials. As natural carbohydrate polymer, cellulose fibers have potential applications in the area due to their biodegradability and flexibility. However, their conductive and electrochemical properties are impossible to meet the demands of practical applications. In this study, cellulose fibers were combined with polyaniline to develop novel paper-based supercapacitor electrode material. Cellulose fibers were firstly coordinated to Cu(II) and subsequently involved in polymerization of polyaniline. Not only the mass loading of polyaniline was significantly increased, but also an impressive area specific capacitance (2767 mF/cm 2 at 1 mA/cm 2 ) was achieved. The developed strategy is efficient, environmentally friendly, and has implications for the development of cellulosic paper-based advanced functional materials.
研究领域:
材料科学
·
能源存储
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRIBOLOGY INTERNATIONAL
·
2023
·
IF 6.2
Pei Wang,Fengminyu Xie,David Wexler,Jian Yin,Hongbo Zhang,Hongtao Zhu
Copper fiber reinforced carbon/carbon composite (C/C-Cuf) and copper alloy impregnating carbon/carbon (C/C-Cu) composite as promising materials of pantograph strip were fabricated and investigated for tribological behaviors and relevant mechanisms, comparing results with pure carbon strip currently used in high-speed railway. C/C-Cuf composite and C/C-Cu composite have more advantage than the pure carbon strip in terms of electric conductivity and mechanical performances. During current-carrying friction tests, C/C-Cu composite has the lowest arc discharge energy and smoothest worn surface. It is attributed that suitable heat treatment decreases the interlaminar defects (Covalent cross-bonds and sp 3 structure) of amorphous carbon , and the tribolayer with grapheme-like structure is formed through the processes of rehybridization, rearrangement and reorganization on the worn surface of C/C-Cu composite.
研究领域:
材料科学
·
机械工程
·
电气工程
·
表面科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）