Catalysts
·
2017
·Vol. 7
·期 10
·302
·
IF 3.082
Ni Tu,Jianxin Shou,Huaping Dong,Jin Huang,Yimin Li
Clay/chitosan composite beads were prepared and used as the carrier to support lipase by adsorption, to improve the activity and stability of lipase in the hydrolysis of olive oil. Under conditions of pH 6.0, 25 °C and adsorption for 10 h, immobilized lipases on chitosan bead (CB–lipase) and three clay/chitosan composite beads, at different clay to chitosan proportions of 1:8 (CCB-8-lipase), 1:5 (CCB-5-lipase) and 1:3 (CCB-3-lipase), were prepared. By comparing the activity of these immobilized lipases, CCB-5-lipase showed the highest activity, followed by CCB-8-lipase > CCB-3-lipase > CB-lipase; this improvement was attributed to the synergetic effect of enrichment of olive oil by clay at the reaction surface and better biocompatibility of chitosan with lipase molecules. The optimum pH and temperature in the reaction respectively changed from 7.0 and 30 °C for free lipase to 7.5 and 35 °C for immobilized forms. Furthermore, the thermal stability and repeated usability of these immobilized lipases were sequenced as CCB-3-lipase > CCB-5-lipase > CCB-8-lipase > CB–lipase, due to greater rigidity of immobilized lipase with the addition of clay, which was further confirmed by SEM. The study shows that the incorporation of clay with chitosan creates a good synergetic effect to improve the catalytic performance of immobilized lipase on clay/chitosan composite.
研究领域:
生物催化
·
酶工程
·
材料科学
·
应用微生物学
·
分子生物学
✓ 已验证
DOI
高影响因子
NPG Asia Materials
·
2015
·Vol. 7
·期 1
·e158
·
IF 10.118
Wang Xiao,Liu Dapeng,Li Junqi,Zhen Jiangman,Zhang Hongjie
The fabrication of multi-component hybrid nanostructures is of vital importance because their two-phase interface could provide a rich environment for redox reactions, which are beneficial for enhancing catalytic performance. Inspired by the above consideration, strongly coupled Cu 2 O@CeO 2 core@shell nanostructures have been successfully prepared via a non-organic and clean aqueous route without using any organic additive. In this process, an auto-catalytic redox reaction occurred on the two-phase interface, followed by a triggered self-assembly process. Additionally, the size, morphology and composition of the as-obtained nanostructures can be tuned well by varying the reaction temperature, as well as the species and the amount of Cu precursors. The catalytic tests for peroxidase-like activity and CO oxidation have been conducted in detail, and the results confirm a strong synergistic effect at the interface sites between the CeO 2 and Cu 2 O components.
研究领域:
材料化学
·
纳米催化
·
界面科学
·
无机合成
·
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
JOURNAL OF THE ENERGY INSTITUTE
·
2021
·
IF 6.186
Dongjing Liu,Lingtao Yang,Bin Li,Jiang Wu
Rice husk , as an abundant agricultural waste and renewable biomass, is adopted to produce porous silica which is used as a potential carbon-free adsorbent for mercury emission control of coal-fired power plants. The rice husk derived porous silica (RHS) exhibits a good Hg 0 adsorption capability with Hg 0 removal efficiency above 80% in the temperature range of 60–140 °C, which is plausibly due to the big specific surface area and mesoporous structure. The mercury removal performance of RHS can be evidently reinforced by KBr modification. The optimal KBr loading value and reaction temperature are 2 wt% and 140 °C, respectively. Acidic gas components, such as NO and SO 2 , both show slight inhibitive effects on Hg 0 adsorption process probably owing to the competitive adsorption or the elimination of adsorption sites.
研究领域:
环境科学
·
大气污染控制
·
材料科学
·
吸附技术
·
能源工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Ruxia Ning,Xichuang Cheng,Fuhou Lei,Jiufang Duan,Kun Wang,Jianxin Jiang
Natural and high-quality biomass-based coating films are considered promising packaging to consumers. However, the poor mechanical properties and weak antimicrobial activity of biomass materials have limited their practical application. A cleaner and low-cost strategy is used to prepare antimicrobial, self-recovery, and biocompatible coating films using tamarind kernel powder (TKP) and chitosan (CS). The TKP protein and chitosan chains were covalently cross-linked with tetrakis(hydroxymethyl)phosphonium chloride (THPC) to form a three-dimensional network based on THPC-amine dynamic bonds, and act as a sacrificial bond. Then, the hydrogen bond forms an interpenetrating network to build a strong multi-network film. Thus, the THPC multi-crosslinking TKP based films showed enhanced stretchable property (increased from 3.23 % to 77.54 %), and self-recovery after 30 min of recovery. Additionally, the film has been found to exhibit low water vapor permeability, low oxygen transmittance rate, and excellent antimicrobial efficiency (maximum inhibition zones: 24.39 mm). Moreover, the prepared films were demonstrated to be biocompatible and non-hemolytic based on cell viability and hemolytic activity assays. The method described herein could broaden the scope of biomass-based materials in the realm of antimicrobial coating films.
研究领域:
高分子材料科学
·
食品包装工程
·
生物医学材料
·
天然高分子化学
·
抗菌材料
·
可再生资源利用
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 48
·期 3
·3636-3646
·
IF 4.527
Shunxiang Wang,Songwen Fang,Kexiang Zhang,Yongjin Zou,Zuoan Xiao,Fen Xu,Lixian Sun,Cuili Xiang
A poor electrical conductivity and short cycle life limits the wide application of transition metal oxides in energy storage applications. In this study, yolk-shell structured CuCo 2 S 4 was grown on NiO nanosheets (NiO@CuCo 2 S 4 ) via a hydrothermal method and vulcanization , which combined the synergistic interactions between Ni, Co, and Cu. The effect of varying the amount of the vulcanizing agent (thiourea) on the electrochemical performance of NiO@CuCo 2 S 4 was also investigated. Moreover, the amount of thiourea not only tuned the morphology of the composite, but significantly influenced its electrochemical performance. When the Cu 2+ : Co 2+ : thiourea molar ratio in the precursor solution was 1:2:6, the obtained NiO@CuCo 2 S 4 exhibited the best electrochemical performance of the various systems examined, with a specific capacitance of 1658 F g −1 being achieved at 1 A g −1 . Density functional theory calculations further confirmed the excellent synergistic effect between NiO and CuCo 2 S 4 . In addition, the asymmetric supercapacitor composed of a NiO@CuCo 2 S 4 positive electrode reached an ultrahigh energy density of 73 Wh kg −1 at a power density of 802 W kg −1 , as well as excellent cycling stability (i.e., 91% capacitance retention after 5000 cycles). These results suggest that NiO@CuCo 2 S 4 is a promising candidate for use in energy storage applications.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2024
·Vol. 31
·期 3
·1-10
·
IF 2.6
You Pingfeng,Zhang Ping,Chen Pengfei,Xie Ruishi,Chen Lin,Xiong Ying
With the rapid development of society, polymer materials are widely used in automotive, construction, and electronic components due to their excellent properties such as easy processing, cheap price, and corrosion resistance. However, most polymers, such as rubber and leather, suffer from poor mechanical properties, susceptibility to micro cracking and flammability. In this paper, an epoxidized natural rubber (ENR)/polylactic acid (PLA)/chitosan (CS)/guanidine phosphate (GP) composites with certain self-healing and flame-retardant properties are successfully prepared. The network structure is constructed by forming thermoplastic elastomers (TVPs) through ENR and PLA, and the amino groups on CS and GP can form hydrogen bonds with ENR, which improves the mechanical properties of ENR/PLA composites and gives the ENR/PLA/CS/GP composites excellent self-healing properties. Meanwhile, CS and GP can also form intumescent flame retardants to improve the flame-retardant properties of ENR/PLA composites. The results show that the mechanical strength of ENR/ PLA /CS/GP composites can reach 4.2 MPa when the addition of CS and GP is 2phr and 4phr, respectively. The self-healing effectiveness of the ENR/PLA/CS/GP composite reaches up to 78% after 3 h at 130 °C. The stress intensity of the original ENR/PLA composite is 3.4Mpa, and that of healing ENR/PLA/CS/GP composite is 3.3Mpa. Meanwhile, the peak heat release rate (HRR) of ENR/PLA could decease 35.8% owing to 2phr CS and 4phr GP.
研究领域:
高分子科学
·
材料工程
·
化学工程
·
纳米技术
✓ 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
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Zhenting Zhao,Yueyun Huang,Qiuguo Li,Haijuan Mei,Fanglong Zhu,Weiping Gong
We demonstrate the fabrication of Co 3 O 4 (derived from zeolitic imidazolate framework-67) wrapped Ag nanowires core-shell nanostructures, and support it on graphene matrix (Co 3 O 4 @Ag NWs-GR) to prepare enzymeless glucose sensor. The core-shell Co 3 O 4 @Ag nanowires possess porous surface and the proposed Co 3 O 4 @Ag NWs-GR nanocomposites exhibit hierarchical structure which could help to improve the performance of enzyme-free glucose detection. For practical application, the as-prepared Co 3 O 4 @Ag NWs-GR nanocomposites were sandwiched by nickel foam (NF) to develop a glucose detection electrode, which demonstrates good reproducibility and glucose specific selectivity. Then, the Co 3 O 4 @Ag NWs-GR/NF electrode was integrated with Pt wire, Ag/AgCl wire and polydimethylsiloxane (PDMS) to fabricate a sensitive device. The amperometric response of the as-developed device suggests that the Co 3 O 4 @Ag NWs-GR/NF based sensor presents a high sensitivity of 2.49 μA/μM/cm 2 in the linear interval of 3–2000 μM, a detection limit of 0.98 μM, as well as an outstanding long-term stability. Additionally, the human serum was used to verify that the Co 3 O 4 @Ag NWs-GR based glucose sensor can detect the glucose level in serum, suggesting it is applicable to the enzymeless glucose determination.
研究领域:
生物医学工程
·
纳米医学
·
电化学传感
·
糖尿病监测
·
转化医学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Xing-Liang Yin,Lei-Lei Li,Jian-Hua Jiang,Xin-Xin Du,Dong-Hui Pang,Jie Yang,Zhong-Jia Li,Yuan-Xu Wang,Xin-Yue Li,Da-Cheng Li,Jian-Min Dou
Photocatalytic H 2 evolution from water splitting offers an attractive scientific and technological method to address the energy and environmental crisis. In this study, noble-metal-free Zn 0.5 Cd 0.5 S@MoS 2 core@shell nanoheterostructures were elaborately designed and successfully synthesized. The visible-light-driven photocatalytic performance investigation shows that the Zn 0.5 Cd 0.5 S@MoS 2 exhibits a state-of-the-art H 2 evolution rate of 40.2 mmol g −1 h −1 far exceeding that of pristine Zn 0.5 Cd 0.5 S by more than 57 times. Moreover, thanks to the protection of MoS 2 shells, the Zn 0.5 Cd 0.5 S@MoS 2 can retain long-term stability in four-cycles of 24 h reactions. Furthermore, a tentative mechanism on H 2 generation was systematically investigated and proposed, which contributes to understand the enhanced photocatalytic activity of the Zn 0.5 Cd 0.5 S@MoS 2 heterostructures and may inspire the synthesis of other desirable catalytic systems.
研究领域:
材料科学
·
物理化学
·
能源化学
·
纳米催化
·
光化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）