POLYMER COMPOSITES
·
2017
·Vol. 39
·期 10
·3676-3685
·
IF 2.324
Juan Gong,Weihong Guo,Kai Wang,Jiaoyang Xiong
In order to enhance the adhesion and compatibility of magnesium hydroxide sulfate hydrate (MHSH) whiskers with polyvinyl chloride (PVC), and prepare high performance MHSH/PVC composites, chitosan (CS) is coated on the surface of MHSH whiskers by a facile method. The effect of the CS-coated MHSH (CS-MHSH) whisker and its toughness and reinforcement for PVC are studied. A thin layer coated on the surface of MHSH whiskers after modification is investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The efficacy of surface modification is confirmed by fourier transform infrared spectroscopy (FTIR), X-ray power diffraction analyses (XRD) and energy disperse spectroscopy (EDS). The optimum modification concentration of CS is 0.025%. The notched impact strength and flexural modulus of PVC composite with 15 phr CS-MHSH whiskers are increased by 85.5% and 58.5% compared with those of pure PVC, and by 48.3% and 4.1% compared with those of the PVC composite with 15 phr unmodified MHSH whiskers. A better thermal stability of CS-MHSH/PVC composite is showed by thermogravimetric analysis (TGA). Dynamic mechanical analysis (DMA) result indicates that CS-MHSH whiskers have a better dispersion and a stronger interfacial adhesion with PVC matrix. POLYM. COMPOS., 39:3676–3685, 2018. © 2017 Society of Plastics Engineers
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Yanrong Wang,Hui Huang,Qingshui Xie,Yuanpeng Wang,Baihua Qu
Sodium-ion batteries (SIBs) have gained more and more interest for grid-level energy storage applications compared with current lithium-ion batteries (LIBs). In this paper, well-uniform and dispersed spindle-shaped NiCo 2 O 4 particles were synthesized by solvothermal method, and then graphene-encapsulated NiCo 2 O 4 (NiCo 2 O 4 @G) was formed core-shell nanostructures , which greatly enhanced the electronic and ionic (electro-active) conduction and also effectively buffering to accommodate the strain. Benefit from its structure feature, the prepared NiCo 2 O 4 @G core-shell nanostructures composite shows good cycling with a capacity of up to ∼400 mAh g −1 (100 mA g −1 ) in 100 cycles for NIBs anode. The facile synthesis process and excellent SIBs behaviors in this paper are expected to be extended in developing other anode materials in battery system.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
CARBON
·
2018
·
IF 7.082
Guoliang Liu,Zhiming Liu,Jinlei Li,Min Zeng,Zhiyun Li,Lin He,Fuwei Li
Development of heteroatom-doped porous carbon frameworks derived from renewable biomaterials is highly desirable. Here we report phytic acid-chitosan (PA-CS) hydrogel as a platform for facile preparation of N, P dual-doped porous carbon networks via direct pyrolysis . The hydrogel system shows great versatility towards incorporating graphene oxide or metal ions, providing a way to introduce graphene sheets or metal nanoparticles into carbon matrix as needed. After the incorporation of graphene, the obtained N, P dual-doped carbon/graphene (NPC/G) sample shows a large specific surface area (1824 m 2 g −1 ), with a mixed meso- and micro-pore volume of 1.04 cm 3 g −1 . Importantly, the NPC/G sample exhibits high activity towards electrochemical oxygen reduction reaction in both alkaline and acidic electrolyte, ensuring a high-performance air catalyst of primary zinc-air batteries. Hopefully, this work provides a new method for the preparation of porous carbon materials with desired properties for catalysis.
研究领域:
材料科学
·
电化学
·
能源化学
·
纳米催化
·
可再生能源
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2016
·
IF 8.328
Aiping Wu,Chungui Tian,Yanqing Jiao,Qing Yan,Guoyu Yang,Honggang Fu
The visible-light driven, Pt-free photocatalytic H 2 evolution (PHE) is promising for clean and sustainable H 2 production. The construction of the heterojunction structure with intimate contact and good light adsorption ability is important for realizing the high effective PHE. Here, the core-shell structured MoS 2 /CdS hybrids were constructed through “sequential two-step hydrothermal growth” route for Pt-free PHE. In the synthesis, the hierarchical flower-like MoS 2 was firstly obtained through the reaction of ammonium molybdate and excessive thiourea. Subsequently, without need of centrifugation, the cadmium acetate (Cd source) was added into the cooled MoS 2 solution directly followed by a secondary hydrothermal reaction. In the process, the Cd 2+ could react with partially S 2− in MoS 2 (substituted reaction) and with the excessive S 2− ions in solution to generate CdS, resulting in the formation of CdS shell contacted with MoS 2 core. The micro-structure of the composites (such as the thickness and morphology of CdS shell) could be tuned by changing the amount of Mo source and Cd source. In the composites, the CdS on the outside is convenient to absorb the solar light. The intimate contact of CdS and MoS 2 is beneficial to charge transfer. As a result, the MoS 2 /CdS catalyst showed high catalytic activity for PHE under visible light irradiation (λ > 420 nm). The H 2 evolution rate could reach to 775 μmol h −1 (20 mg catalyst), which is much higher than pure CdS (12 μmol h −1 ) and Pt-CdS (64 μmol h −1 ). The good activity should be related with CdS outside shell beneficial for light adsorption and intimate contact of CdS and MoS 2 for easy charge transfer. A series of experiments demonstrate that the formation of the heterojunction can effectively enhance the charge transfer ability and retard the recombination of electron-hole pairs, thus improving PHE activity and alleviating the photocorrosion of CdS component.
研究领域:
材料科学
·
光催化
·
能源化学
·
纳米材料
·
可持续能源
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2021
·
IF 6.024
Wangwu Li,Jiao Peng,Hui Li,Zhenyu Wu,Yuehua Huang,Baobao Chang,Xiaowei Guo,Gairong Chen,Xianyou Wang
At present, the main limitations for the practical application of silicon (Si) as an anode material of a lithium-ion battery are huge volume variation and low electrical conductivity. Core–shell silicon/carbon (Si/C) composites can greatly relieve the Si large volume change and accelerate the low Li+ conductivity; however, cracking of carbon shell and the failure of the electrode structure still limit the lithium storage capability and cyclic life. Herein, a flexible freestanding N-doped core–shell Si/C nanofiber (SC-NF) anode is prepared by the double-nozzle electrospinning technique. It has been found that in such fibers, Si particles are encapsulated by the carbon shell of fibers, which can settle the shortcomings of pulverization and volume variation of Si. Furthermore, the highly conductive N–C shell derived from carbonized PAN can accelerate the diffusion of Li+ and charge transport. As a result, the as-prepared core–shell SC-NF-0.24 electrode exhibits an initial specific discharge capacity of 1441 mAh g–1 with a high capacity retention of 76.9% at 0.5 A g–1, and the capacity decay rate of per cycle is only 0.1% (starting on the third cycle), showing a good cycle property. Therefore, the as-prepared freestanding core–shell SC-NF material is a prospective anode material for high-performance lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
·
复合材料
✓ 已验证
DOI
高影响因子
BULLETIN OF MATERIALS SCIENCE
·
2023
·Vol. 46
·期 2
·1-10
·
IF 1.8
Liang Dong,Xiong Sang,Zhang Xiaomeng,Ye Yuanfeng,Cao Jingxin,Hu Xingxing,Song Yao,Wei Qianwen
WO 3 :Eu 3+ powder was prepared by microemulsion method with cetyltrimethyl ammonium bromide (CTAB) as a surfactant. The prepared WO 3 :Eu 3+ samples were wrapped with SiO 2 by a coating method. The WO 3 :Eu 3+ @ SiO 2 nanocomposites with the core-shell structure were prepared by controlling tetraethyl orthosilicate (TEOS) content (1, 3, 5 and 7%) and water–alcohol ratio (1:3, 1:1.5, 1:1 and 2:1). The structure, morphology and luminescence properties of the prepared WO 3 :Eu 3+ @ SiO 2 samples were characterized by XRD, SEM, TEM and fluorescence spectra. The results show that the prepared WO 3 :Eu 3+ @SiO 2 nanocomposites are spherical and granular, and the average particle size is below 100 nm. Under the condition of different TEOS contents, the strongest characteristic peak is located at 554 nm in the green light band at the excitation wavelength of 328 nm. Among the different water–alcohol ratio conditions, the prepared WO 3 :Eu 3+ @SiO 2 nanocomposite has the strongest luminescence intensity at the water–alcohol ratio of 1:3, and the excitation wavelength is 328 nm. The excitation spectra measured at 612 nm have prominent characteristic peaks at 362, 394, 422, 465 and 499 nm, which correspond to the transition of 7 F 0 → 5 D 4 , 7 F 0 → 5 L 6 , 7 F 0 → 5 D 3 , 7 F 0 → 5 D 2 and 7 F 0 → 5 D 1 , respectively.
研究领域:
材料科学
·
纳米技术
·
光学性质
✓ 已验证
DOI
高影响因子
FDMP-Fluid Dynamics & Materials Processing
·
2022
·
IF 0
Chao Wei,Zhongjin Peng,Yunfei Chen,Yanhai Cheng
Ag 3 PO 4 exhibits a high photocatalytic activity if exposed to visible light, however, it displays bottlenecks such as poor cycle-stability and mediocre ability to degrade methyl orange (MO) because of limited adsorption of MO molecules onto its surface. In this study, nano TiO 2 prepared by a one-step method was combined with Ag 3 PO 4 to form a TiO 2 @Ag 3 PO 4 heterojunction in order to improve this material both in terms of photocatalysis and photostability. After adding a KH-570 silane coupling agent, the photocatalytic performance of TiO 2 @Ag 3 PO 4 could be improved even further, with the degradation rate of MO maintained at more than 90% after three cycles of visible in light.
研究领域:
材料科学
·
纳米技术
·
环境科学
·
化学工程
✓ 已验证
DOI
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Zehao Jin,Lili Wang,Kaiyuan Zheng,Qiyue Gao,Wei Feng,Shoukang Hu,Ming Yue,Xiaobiao Shan
The triboelectric nanogenerator (TENG) of natural biomaterials is a new type of energy harvesting device and can be used as a self-powered sensor, which has received extensive research and attention. In this paper, based on the biocompatibility of chitosan and chondroitin sulfate, ZnO-modified chitosan/chondroitin sulfate/ZnO TENG was prepared for research on wearable devices and sustainable power supply devices. This study employs molecular dynamics to compute the interaction energy between chitosan and ZnO molecules. Theoretical calculations have unequivocally substantiated the occurrence of a binding interaction between these two molecular entities. The effect of ZnO on chitosan/chondroitin sulfate morphology was investigated by atomic force microscopy . The chitosan/chondroitin sulfate/ZnO TENG has high flexibility and electrical output performance. It can reach 105 V and 3.3 µA of open-circuit voltage and short-circuit current. Chitosan/chondroitin Sulfate/ZnO TENG successfully converts the mechanical energy of human motion into electrical energy. Strong electrical signals are exhibited when making fists and waving fingers and wrists. The TENG is a self-powered source and lights up 70 blue light-emitting diodes (LEDs). The chitosan/chondroitin sulfate/ZnO TENG has demonstrated its capabilities in energy harvesting and wearable self-powered sensors.
研究领域:
材料科学
·
生物医学工程
·
能源技术
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2014
·
IF 4.517
Gong Cheng,Ping Chen,Zhi-Gang Wang,Xiao-Jing Sui,Ji-Lin Zhang,Jia-Zuan Ni
A simple, fast, efficient, and reusable microwave-assisted tryptic digestion system which was constructed by immobilization of trypsin onto porous core-shell Fe 3 O 4 @fTiO 2 microspheres has been developed. The nanostructure with magnetic core and titania shell has multiple pore sizes (2.4 and 15.0 nm), high pore volume (0.25 cm 3 g −1 ), and large surface area (50.45 m 2 g −1 ). For the proteins, the system can realize fast and efficient microwave-assisted tryptic digestion. Various standard proteins (e.g., cytochrome c (cyt-c), myoglobin (MYO), β-lactoglobulin (β-LG), and bovine serum albumin (BSA)) used can be digested in 45 s under microwave radiation, and they can be confidently identified by mass spectrometry (MS) analysis; even the concentration of substrate is as low as 5 ng μL −1 . Furthermore, the system for the 45 s microwave-assisted tryptic digestion is still effective after the trypsin-immobilized microspheres have been reused for 5 times. Importantly, 1715 unique proteins from 10 μg mouse brain proteins can be identified with high confidence after treatment of 45 s microwave-assisted tryptic digestion.
研究领域:
生物化学
·
分析化学
·
蛋白质组学
✓ 已验证
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2023
·
IF 10.9
Yixuan Wang,Canhui Zhang,Xingkun Wang,Jiarui Duan,Kecheng Tong,Shuixing Dai,Lei Chu,Minghua Huang
With the depletion of fossil fuel resources and the increasing severity of environmental pollution, it has become imperative to seek energy conversion devices with low cost, high efficiency and excellent environmental compatibility. Considering their high theoretical energy density, affordability and environmentally friendly nature, Zn-air batteries (ZABs) are regarded as promising energy storage and conversion devices. The utilization of seawater in ZABs (S-ZABs) holds great potential, given the abundance of seawater reserves, offering economic and social benefits such as reducing electrolyte costs and alleviating competition for freshwater consumption in human activities. However, the application of S-ZABs remains challenging, particularly in constructing high-performance cathode oxygen reduction reaction (ORR) catalysts that are highly resistant to Cl − corrosion in seawater-based electrolytes. In this study, we have engineered an ultrathin carbon-chainmail-shell encapsulated Co 9 Se 8 nanoparticles on N-doped mesoporous carbon (named as NMC-Co 9 Se 8 ) electrocatalysts using the high-temperature selenization strategy. The ultrathin carbon-chainmail-shell on the outside improves electron transfer during the electrocatalysis and suppresses nanoparticles agglomeration. Additionally, it could act as armor for protecting the inner active site from the adsorption of corrosive Cl − . Benefit from this unique structure, the NMC-Co 9 Se 8 catalyst exhibits excellent ORR performance, with an onset potential of 0.904 V and a half-wave potential of 0.860 V in seawater-based electrolytes. The catalyst also affords the lowest Tafel slope (35.5 mV·dec −1 ) and the highest kinetics current density of 9.816 mA·cm −2 at 0.85 V among all investigated samples. Owing to the protective effect of the ultrathin carbon-chainmailshell on the inner active sites, the NMC-Co 9 Se 8 catalyst retains 91.6% of its initial activity after continuous operation for 50000 s, surpassing the commercial Pt/C catalyst (with a current retention rate of 62.8%). More importantly, the S-ZABs based on the NMC-Co 9 Se 8 catalyst deliver a high maximum power density of 172.4 mW·cm −2 and a high specific capacity of 643.9 mAh·g −1 , exceeding those of S-ZABs powered by the commercial Pt/C catalyst (151.2 mW·cm −2 and 548.3 mAh·g −1 ). Furthermore, the S-ZABs driven by the NMC-Co 9 Se 8 catalyst demonstrate a discharge stability for up to 150 h and maintain a stable charge-discharge cycle stability over 200 h, demonstrating the practical application performance of the NMC-Co 9 Se 8 catalyst. In practical applications, the S-ZABs driven by the NMC-Co 9 Se 8 catalyst can illuminate a light-emitting diode (LED) with a driving voltage of 2 V for several hours. This work provides new ideas for developing efficient and durable catalysts with high Cl − corrosion resistance for applications in seawater-based Zn-air batteries and other energy conversion technologies. Download: Download high-res image (142KB) Download: Download full-size image
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS CHEMISTRY
·
2012
·Vol. 22
·期 15
·7291-7299
·
IF 5.968
Jungang Hou,Zheng Wang,Wenbin Kan,Shuqiang Jiao,Hongmin Zhu,R. V. Kumar
Large-scale hydrogen production through water splitting using photocatalysts with solar energy can potentially produce clean fuel from renewable resources. In this work, photocatalytic evolution of H2 with a high efficiency was achieved using graphene oxide (GO) nanosheets decorated with CdS sensitized TaON core–shell composites (GO–CdS@TaON). The CdS@TaON core–shell nanocomposites were prepared by an ion-exchange route with assistance from a hydrothermal process on GO as the support. The TaON core–shell composites containing 1 wt% CdS nanocrystals showed a high rate of H2-production at 306 μmol h−1 with an apparent quantum efficiency (QE) of 15% under 420 nm monochromatic light. The rate of hydrogen formation was 68 times faster in comparison with the rate observed on pure TaON. The rate was further increased to 633 μmol h−1 with a high quantum efficiency of 31% when the GO–CdS@TaON hybrid composite was coupled with 1 wt% of graphene oxide and 0.4 wt% of Pt (about 141 times higher than that of the pristine TaON). This high photocatalytic H2-production activity is ascribed firstly to the presence of CdS nanocrystals that alter the energy levels of the conduction and valence bands in the coupled semiconductor system; secondly to the involvement of graphene oxide that serves as an electron collector and transporter to efficiently lengthen the lifetime of the photogenerated charge carriers from CdS@TaON composites. This investigation can open up new possibilities for the development of highly efficient TaON-based photocatalysts that utilize visible light as an energy source.
研究领域:
材料化学
·
光催化
·
能源科学
·
纳米材料
·
半导体物理
·
可再生能源
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Xiang Li,Huaili Zheng,Yili Wang,Yongjun Sun,Bincheng Xu,Chuanliang Zhao
Modified natural polymer flocculants has been the focus of research in environmental engineering field. Natural large molecular compound, chitosan (CTS) with many functional amino and hydroxyl groups can be easily modified to enhance its original functions. This work presents an environmentally friendly chitosan-based cationic polyacrylamide flocculants (CTS-g-PAMA) with enhanced function of sterilization and flocculation . CTS-g-PAMA was synthesized through Ultraviolet (UV)-initiated copolymerization. Structure characterization of FTIR, 1 H NMR, XRD and UV spectrum confirmed the successful grafting of AM and MAPTAC. Scanning electron microscopy (SEM) analysis results showed that CTS-g-PAMA exhibited a porous structure with a prodigious surface area. CTS-g-PAMA was then applied to treat a series of simulated waste water containing kaolin or Escherichia coli . Flocculation tests indicated that CTS-g-PAMA not only showed excellent flocculation effect but also showed high sterilization capability. A series of ONP concentration measurement tests through UV spectra analysis and 3D EEM analysis of suspension before and after flocculation were conducted to study sterilization mechanism, and results revealed the sterilization effect of CTS-g-PAMA was essentially bactericidal, not just antibacterial.
研究领域:
环境工程
·
高分子化学
·
水处理技术
·
材料科学
·
微生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）