RSC Advances
·
2016
·Vol. 6
·期 85
·81767-81773
·
IF 3.289
Jiaxun Hu,Shuqing Wu,Qin Cao,Wenda Zhang
A facile approach was developed to synthesize core–shell structured alumina/Cu microspheres by means of activation by silver nanoparticles in situ deposited on the polydopamine-coated alumina microsphere surface. This approach takes advantage of both the sufficient reductive capacity of polydopamine towards silver ions and the high activation of silver nanoparticles towards copper deposition. The chemical compositions of composite microspheres were characterized by energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR). The surface morphologies and crystalline structures of the coated alumina were studied by field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD), respectively. The adhesion strength between the copper layer and the substrate was evaluated by ultrasonic exposure and thermal shock test. The results showed that silver nanoparticles effectively catalyzed the copper deposition reaction on the polydopamine-coated surface, which led to a faster and more reliable plating process compared with the process without activation. The compact and continuous copper layer obtained showed strong adhesion on the substrate surface.
研究领域:
材料科学
·
纳米技术
·
表面工程
·
复合材料
·
功能材料
✓ 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
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
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光催化
·
能源科学
·
纳米材料
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半导体物理
·
可再生能源
✓ 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
MATERIALS LETTERS
·
2013
·
IF 2.224
Kejie Yu,Xuebin Zhang,Hongwu Tong,Xiangyan Yan,Shaomin Liu
Fibrous monodisperse core–shell structured Fe 3 O 4 /SiO 2 /KCC-1 nanoparticles were synthesised successfully through a surfactant-templated microemulsion formation process. The structure and morphology of the synthesised nanoparticles were investigated by scanning electron microscopy , transmission electron microscopy , superconducting quantum interference device susceptometer, X-ray diffraction, thermogravimetric analysis and N 2 adsorption/desorption. These nanoparticles showed monodisperse spherical morphology, high magnetism , good thermal stability , large surface area , direct channels, easily accessible large pores and narrow size distribution. A mechanism for the synthesis of these nanoparticles was proposed and explained. Adsorption experiments indicated that the as-prepared materials had good adsorption capacity for dye and could perform a fast transfer of molecules, indicating its promising application in purification of industrial wastewater, drug delivery and so on.
研究领域:
纳米医学
·
材料科学
·
环境工程
·
生物材料
·
药剂学
·
胶体与界面化学
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2016
·
IF 2.437
Yan Fang,Xiaohong Jiang,Lihong Niu,Shujie Wang
Polypyrrole/aligned carbon nanotubes (PPy/ACNTs) core-shell nanotube arrays on metal foil have been fabricated through an electrochemical method. The as-prepared PPy/ACNTs electrode materials with novel nanostructure , which is very conducive to the transmission of electrons and ions, possess greatly improved electrochemical performance. The specific capacitances of PPy/ACNTs electrode materials can reach 505 F/g ( vs. the both mass of PPy and ACNTs) in three-electrode system. In two-electrode system, the specific capacitances of the PPy/ACNTs electrode materials can reach 456 F/g ( vs. the both mass of PPy and ACNTs). The PPy/ACNTs electrode materials also exhibit greatly improved rate capability and superior cycling performance.
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
RSC Advances
·
2016
·Vol. 6
·期 72
·67827-67832
·
IF 3.289
W. X. Chen,J. S. Yu,W. Hu,Z. L. Chen,H. Memon,G. L. Chen
A core/shell heterostructured nanonanocomposite catalyst based on NiO nanoflakes and titanate nanowires (TNWs) was fabricated. The experimental results showed that the precursor concentration and the reaction time for NiO deposition played significant roles in determining the resulting heterostructure, and an optimal precursor's concentration would result in a well-defined core/shell heterostructure. The XRD analysis demonstrated the existence of the (1 1 1), (2 0 0) and (3 1 1) lattice planes of the NiO nanoflakes. Nearly 100% of the MB pollutant (10 mg L−1) was photodegradaded by the TNWs/NiO catalyst within 50 minutes under UV light irradiation.
研究领域:
材料化学
·
环境催化
·
纳米材料科学
·
光催化降解
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Xingliang Chen,Yan Wang,Hailing Liu,Shu Jin,Guanglei Wu
The applications of cobalt ferrite and nickel ferrite composite materials on electromagnetic (EM) wave absorption are the research hotspot currently. However, the systematical comparison study between these two ferrites composites have rarely been carried out. Thus, the EM wave absorption performance of interconnected carbon@Ni x Co 1-x Fe 2 O 4 composites with core–shell structures were investigated comprehensively in this work. A series of magnetic nanospheres including NiFe 2 O 4 , cobalt-doped nickel ferrite, nickel–cobalt ferrite, nickel-doped cobalt ferrite and CoFe 2 O 4 were synthesized firstly, and then uniformly encapsulation by carbon rendered the corresponding C@Ni x Co 1-x Fe 2 O 4 composites nanospheres. Synthesis reactions involved for C@Ni x Co 1-x Fe 2 O 4 formation were investigated in detail, and afterwards their magnetic behavior, EM wave absorption performance and absorbing mechanism were thoroughly explored and analyzed. Results show that when nickel is dominant element and cobalt is doping element (Ni 0.75 Co 0.25 Fe 2 O 4 ), the composite nanosphere exhibits optimum EM wave absorption performance. When the sample thickness is just 1.9 mm, its RL min value can reach −51 dB, and the corresponding EAB width is 3.3 GHz. The synthesized C@Ni 0.75 Co 0.25 Fe 2 O 4 can be qualified as an efficient and thin electromagnetic wave absorber, which is mainly attributed to its special structure, fair electromagnetic matching and impedance matching.
研究领域:
材料科学
·
电磁学
·
纳米材料
·
功能材料
·
复合材料工程
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2016
·
IF 3.997
XinRong Liu,Ming Zhang,TingTing Yang,LiNa Wang,Han Zhu,ShunLi Wang,MingLiang Du
Carbon nanofibers served as nanoreactors for the design and construction of PtCo alloy carbon core-shell nanostructures with nitrogen doping (PtCo/NCNF) through a combination of electrospinning and nitrogen doping treatments. The PtCo/NCNF hybrid consists of PtCo alloy nanoparticles surrounded by a few of N-doped carbon layers , demonstrating a typical core-shell structures. The PtCo/NCNF hybrid can both served as electrode materials for electrocatalytic water splitting including hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). For the HER performance, the PtCo/NCNF exhibits very small onset potential of 20 mV, an overpotential of 50 mV at a j (vs RHE) = 10 mA cm − 2 and Tafel slope of 30 mV dec − 1 . The PtCo/NCNF hybrid also exhibits high OER activity with an onset potential of 310 mV, an overpotential of 400 mV at a j of 10 mA cm − 2 and a small Tafel slope of 76 mV dec − 1 . The high catalytic activities of PtCo alloy for HER and OER originate from the 3D hierarchical structures, well-dispersed PtCo alloy, high conductivity of NCNF, protection from the carbon-encapsulated structure, and the introduction of nitrogen.
研究领域:
材料科学
·
纳米技术
·
电化学
·
能源化学
·
催化化学
·
功能材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Shunhang Wei,Rong Wu,Xiaoxiang Xu,Jikang Jian,Haixia Wang,Yanfei Sun
Black core-shelled anatase titania were successfully prepared using a simple one-step synthetic method by calcining colloid titania precursor in N 2 flow under atmospheric pressure. The physicochemical properties of the as-prepared samples were characterized by various techniques such as X-ray diffraction, high resolution transmission electron microcopy, etc. The samples demonstrate a unique core-shelled structure and electron paramagnetic resonance spectra reveal the presence of high concentration of Ti 3+ and oxygen vacancies at the surface, which accounts for their black appearance. A possible mechanism for the formation of such core–shell structure is proposed based on the results (X-ray photoelectron spectra, etc) of products prepared under different ration between urea and hydrochloric acid. Ethanol absolute is found to have critical effect in preventing phase transition of titania (from anatase to rutile) upon elevated temperatures. The black appearance of the sample powder (high visible light absorption) as well as slow electron/hole recombination rate after introducing oxygen vacancies/N species signify the core-shelled anatase titania as an efficient visible light active photocatalyst.
研究领域:
材料科学
·
光催化
·
纳米材料
·
表面化学
·
无机合成
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 39
·20208-20215
·
IF 3.708
Lei Sun,Xinge Zhang,Jinxia An,Cui Su,Qianqain Guo,Chaoxing Li
Currently, the major challenge for cancer treatment is to develop simple and smart nanocarriers that can efficiently retain the encapsulated drug during blood circulation, recognize tumor cells and quickly release the drug under stimulation. In this paper, such a pH-sensitive core–shell composite nanoparticles is prepared based on a 3-aminophenylboronic acid modified mesoporous silica nanoparticles (MSN–APBA) core coated with a lactobionic acid grafted chitosan (CS–LA) shell via boronate ester bonds. The MSN core increases drug loading capacity and stability, and lactobionic acid offers abundant diols which can form pH sensitive boronate ester bonds with APBA on MSN. Meanwhile, the lactobionic acid-conjugated shell could also efficiently target the asialoglycoprotein receptor over expressing hepatoma cells. The successful synthesis of CS–LA and MSN–APBA is confirmed by the results of TGA, TEM, DLS, FT-IR, 1H-NMR and N2 adsorption–desorption. Doxorubicin hydrochloride (DOX) is applied as a model drug and the behaviors of drug loading/release are investigated. The drug loading behavior is pH-dependent, and its drug encapsulation efficiency is near 80% and loading capacity is 13.05%. The results of cumulative in vitro release indicate that at neutral pH, the pores of the MSN are effectively capped with a polymer shell and the drug release is strongly inhibited, almost zero release. While at acidic pH, the hydrolysis of the boroester bond takes place and thus results in a rapid release of the entrapped drug. The cytotoxicity assay indicates high cell biocompatibility of this material and it is suitable as a drug carrier. When loaded with DOX, it presents distinctly cytotoxic behavior to HepG2 cells, due to the sustained release of drug. These results imply that the core–shell nanoparticles are promising platforms to construct simple and effective pH-responsive controlled drug delivery systems for cancer therapy.
研究领域:
肿瘤学
·
药剂学
·
纳米医学
·
生物材料
·
分子药理学
·
靶向治疗
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Peng Hou,Ke Chen,Xudong Wang,Xiaofei Hu,Bing Li,Ming Liu,Xiao (Matthew) Hu,Yujie Song
The rapid development of high-performance materials has garnered considerable attention in addressing electromagnetic pollution . The construction of core-shell heterostructures is an effective approach for regulating the electromagnetic parameters of absorbers. However, these heterostructures usually lack a direct channel for charge transport between the core phase and the adhesive shell phase. Herein, Fe 2 AlB 2 @FeAl-layered double hydroxides with core-shell heterostructures were prepared using a top-down approach. The tightly connected FeAl-LDHs nanosheets to the Fe 2 AlB 2 parent phase improved electronic transport. Compared with raw Fe 2 AlB 2 , the spherical absorber with an embroidered structure demonstrated stronger reflection loss (-15.6 dB for Fe 2 AlB 2 , −58.6 dB for Fe 2 AlB 2 @FeAl-LDHs) and a broader effective absorption bandwidth (2.2 GHz for Fe 2 AlB 2 , 3.6 GHz for Fe 2 AlB 2 @FeAl-LDHs) due to the enhanced dielectric and magnetic losses. This study presents a practical method for designing new controllable core-shell heterostructures for electromagnetic wave-absorbing materials.
研究领域:
材料科学
·
电磁学
·
纳米材料
·
功能材料
·
复合材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）