ChemSusChem
·
2013
·Vol. 6
·期 10
·1945-1951
·
IF 7.475
Wenjin Wang,Jie Zhang,Shengchun Yang,Bingjun Ding,Xiaoping Song
Graphical Not just another brick in the wall: Brick-like Au@Pd core–shell nanobricks (CNBs) with a concave surface were synthesized through a one-pot procedure, and show an enhanced performance towards ethanol electrooxidation. The improved performance of the CNBs is a result of the exposed stepped surfaces, high-index facets, and the synergistic effects of the core and shell metals. Au@Pd core–shell nanobricks (CNBs) with concave surfaces and Pd shells with a thickness of approximately 5 nm were synthesized by co-reduction of HAuCl 4 and H 2 PdCl 4 in the presence of Au seeds and Ag ions. These as-synthesized concave CNBs exhibit significantly enhanced catalytic activity for the electrooxidation of ethanol in alkaline media compared to the commercially-used Pd black. The improved performance of the Au@Pd CNBs can be attributed to the exposed stepped surfaces, high-index facets, and the synergistic effects of the core and shell metals.
研究领域:
材料科学
·
电化学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Jiangjiexing Wu,Kang Qin,Dan Yuan,Jun Tan,Li Qin,Xuejin Zhang,Hui Wei
One of the current challenges in nanozyme-based nanotechnology is the utilization of multifunctionalities in one material. In this regard, Au@Pt nanoparticles (NPs) with excellent enzyme-mimicking activities due to the Pt shell and unique surface plasmon resonance features from the Au core have attracted enormous research interest. However, the unique surface plasmon resonance features from the Au core have not been widely utilized. The practical problem of the optical-damping nature of Pt hinders the research into the combination of Au@Pt NPs’ enzyme-mimicking properties with their surface-enhanced Raman scattering (SERS) activities. Herein, we rationally tuned the Pt amount to achieve Au@Pt NPs with simultaneous plasmonic and enzyme-mimicking activities. The results showed that Au@Pt NPs with 2.5% Pt produced the highest Raman signal in 2 min, which benefited from the remarkably accelerated catalytic oxidation of 3,3′,5,5′-tetramethylbenzidine with the decorated Pt and strong electric field retained from the Au core for SERS. This study not only demonstrates the great promise of combining bimetallic nanomaterials’ multiple functionalities but also provides rational guidelines to design high-performance nanozymes for potential biomedical applications.
研究领域:
纳米材料科学
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生物医学工程
·
光谱学
✓ 已验证
DOI
高影响因子
ISRAEL JOURNAL OF CHEMISTRY
·
2015
·Vol. 56
·期 4
·242-248
·
IF 2.221
Junwei Zhao,Jian Wu,Junfei Xue,Qiannan Zhu,Weihai Ni
Graphical Colloidal superparticles (SPs) are nanoparticle (NP) assemblies in the form of colloidal particles. Assembling nanoscopic objects into mesoscopic or macroscopic composite architectures allows for the bottom-up fabrication of functional nanomaterials. In this study, a method for single-step self-assembly synthesis of Au/NaYF 4 : Yb,Er SPs was developed using oil-in-water (O/W) microemulsions to simultaneously encapsulate gold nanoparticles (AuNPs) and NaYF 4 : Yb,Er upconversion nanoparticles (UCNPs) via evaporation at room temperature. The synthesized Au/NaYF 4 : Yb,Er SPs possess good dispersibility and stability. When the number of AuNPs added is increased, the SPs exhibit decreased upconversion luminescence, which can be ascribed to the Förster resonance energy transfer (FRET) from the NaYF 4 : Yb,Er UCNPs to the AuNPs. Time-resolved measurements of the green emission further confirm the existence of a new decay route corresponding to the FRET process. Our research provides a facile and versatile strategy for the synthesis of novel multifunctional nanocomposites with tunable upconversion luminescence properties, which can be of great significance in biological applications.
研究领域:
材料科学
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纳米技术
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光学
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生物医学工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Lianjin Chen,Xiaosen Wang,Aimei Zhu,Qiugen Zhang,Qinglin Liu
Direct ethanol fuel cell can convert chemical energy into electric energy directly, and has the advantages of being free from Carnot cycle and being friendly to environment, so it has a broad application prospect. However, the insufficient activity and toxicity resistance of anodic catalysts limit their commercial application, mainly due to the limited adsorption sites and the toxic inactivation of catalysts resulting from the production of toxic intermediates (CO ads ) during the ethanol oxidation reaction (EOR) process. In this study, the Au@PdAg porous hemispherical catalyst assembled by nanotubes was successfully prepared by soft template method and co-reduction method using dioctadecyl dimethyl ammonium chloride (DODAC) as surfactant, and its EOR performance was tested. Au@Pd 1.0 Ag 1.0 has the highest mass current density with a peak value of 4048.8 mA mg Pd − 1 , which is 7.8 times of Pd/C (JM). After 5000 s stability test, the residual current density value is still 863.4 mA mg Pd − 1 . The results showed that the introduction of the oxygenophilic metal Ag was conducive to the formation of OH ads and the oxidation of CO ads . The porous structure of the nanotube assembly facilitates electron transfer and provides more adsorption sites, which makes the catalyst show good electrocatalytic activity and anti-CO poisoning ability.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
TALANTA
·
2016
·
IF 4.035
Hai-Yan Song,Tian-Fang Kang,Li-Ping Lu,Shui-Yuan Cheng
Single or few-layer nanosheets of MoS 2 (MoS 2 nanosheets) and a composite composed of MoS 2 nanosheets, Au nanoparticles (AuNPs) and hemin (HE) (denoted as MoS 2 -Au-HE) were prepared. The composites possessed high synergetic catalysis activity towards the electroreduction of hydrogen peroxide. Furthermore, glucose oxidase (GOD) and AuNPs were used as marker of the complementary DNA (cDNA) strand of kanamycin aptamer to prepare a conjugate (reffered as cDNA-Au-GOD) that was designed as the signal probe. Both cDNA-Au-GOD and MoS 2 -Au-HE were applied to fabricate aptasensor for kanamycin. MoS 2 -Au-HE acted as solid platform for kanamycin aptamer and signal transmitters. AuNPs were employed as the supporter of cDNA and GOD which catalyze dissolved oxygen to produce hydrogen peroxide in the presence of glucose. Then cathodic peak current of H 2 O 2 was recorded by differential pulse voltammetry (DPV). The electrochemical reduction of H 2 O 2 was catalyzed by MoS 2 -Au-HE that was modified onto the surface of a glassy carbon electrode (GCE). The cathodic peak current of H 2 O 2 was highly linearly decreased with an increase of kanamycin concentrations from 1.0 ng/L to 1.0×10 5 ng/L, with a detection limit of 0.8 ng/L. This aptasensor can be used to detect kanamycin in milk with high specificity, sensitivity and selectivity .
研究领域:
生物化学
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分析化学
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纳米技术
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DOI
PubMed
高影响因子
Materials
·
2024
·Vol. 17
·期 2
·509
·
IF 3.1
Shuya Ning,Shuo Wang,Zhihui Liu,Naming Zhang,Bin Yang,Fanghui Zhang
Magnetic–plasmonic nanoparticles (NPs) have attracted great interest in many fields because they can exhibit more physical and chemical properties than individual magnetic or plasmonic NPs. In this work, we synthesized Au- or Ag-decorated Fe3O4nanoparticles coated with PEI (Fe3O4-PEI-M (M = Au or Ag) NPs) using a simple method. The influences of the plasmonic metal NPs’ (Au or Ag) coating density on the magnetic and plasmonic properties of the Fe3O4-PEI-M (M = Au or Ag) NPs were investigated, and the density of the plasmonic metal NPs coated on the Fe3O4NPs surfaces could be adjusted by controlling the polyethyleneimine (PEI) concentration. It showed that the Fe3O4-PEI-M (M = Au or Ag) NPs exhibited both magnetic and plasmonic properties. When the PEI concentration increased from 5 to 35 mg/mL, the coating density of the Au or Ag NPs on the Fe3O4NPs surfaces increased, the corresponding magnetic intensity became weaker, and the plasmonic intensity was stronger. At the same time, the plasmonic resonance peak of the Fe3O4-PEI-M (M = Au or Ag) NPs was red shifted. Therefore, there was an optimal coverage of the plasmonic metal NPs on the Fe3O4NPs surfaces to balance the magnetic and plasmonic properties when the PEI concentration was between 15 and 25 mg/mL. This result can guide the application of the Fe3O4-M (M = Au or Ag) NPs in the biomedical field.
研究领域:
纳米材料科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2021
·
IF 4.098
Xuemin Xia,Yijin Weng,Lei Zhang,Ruyi Tang,Xia Zhang
Surface-Enhanced Raman Scattering (SERS) is a powerful analysis technology, attracting more and more attention due to its high sensitivity and selectivity. Herein, we report a simple seed-mediated method to synthesize Au@Ag nanoparticles (NPs) as a multifunctional biosensor for the label-free detection of hydrogen peroxide (H 2 O 2 ) and glucose by SERS. Au@Ag NPs, as an ultrasensitive SERS substrate, show the dual activities (peroxidase-like and GOx-like activities). Under the condition of pH 4.0 NaAc buffer solution, the glucose and H 2 O can be catalyzed by Au@Ag NPs to produce glucose acid and H 2 O 2 , and then H 2 O 2 can oxidize 3,3′,5,5′-tetramethylbenzidine (TMB) to form a blue oxidation product oxidic TMB (oxTMB) which exhibits strong SERS signals at 1188, 1330, 1605 cm −1 . Thus, we have developed a new SERS strategy for analysis of glucose with a detection limit of 5 × 10 − 10 mol L −1 , suggesting that Au@Ag NPs have the potential for biosensor, immunoassay and medical treatment.
研究领域:
生物传感
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医学检测
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纳米技术
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2024
·
IF 2.7
Kang Shen,Caili Bi,Haifan Yang,Miaowen Xu,Lili Huang,Youwei Wang
Based on the coordination principle of Lewis acid, the 4-mercaptophenylboronic acid (4-MPBA)-modified novel dumbbell-shaped Au-Ag nanorods (4-MPBA@DS Au-AgNRs) substrate has been developed, which could be combined with the surface-enhanced Raman scattering (SERS) technique to detect SO42- with high sensitivity and specificity. DS Au-AgNRs synthesized in this paper with dumbbell particular structure have been verified by finite-difference time domain (FDTD) simulation to be capable of stimulating strong localized electromagnetic enhancement (EM) at nano-edge, gap, generating a large number of “hot spots” exhibiting excellent SERS performance. The 4-MPBA modified on its surface could specifically recognize SO42-, producing a change in the spectral peak at 1382 cm-1, thus realizing highly sensitive and specific sensing of SO42-. Under optimized conditions, this SERS sensor responded rapidly to SO42- within 2 minutes and demonstrated uncommon immunity. Ratio calculation by the ratio of the characteristic peaks at 1382 and 1070 cm-1 (I1382/I1070) enabled quantitative detection of SO42- in the range of 1 × 10-8-1 × 10-3 M, and the detection threshold was as low as 1 nM, which was superior to that of similar detection methods. Importantly, the utility and reliability of this SERS substrate for the determination of SO42- in actual samples were evaluated using ion chromatography as the gold standard, and there was no significant difference between the two protocols (P > 0.05), and the RSD was less than 6% with a satisfactory recovery rate (97.6-102.3%). Therefore, the present protocol has the advantages of simplicity and rapidity, high sensitivity, specificity, stability, and practicability in the determination of SO42- in aqueous solution, providing a reliable solution for tracing SO42- in the field of food safety and environmental testing.
研究领域:
分析化学
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环境科学
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食品安全
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Xiaojing Yu,Haoran Qiu,Bin Wang,Qingnan Meng,Shaodong Sun,Yufei Tang,Kang Zhao
To construct Z-scheme not only can effectively separate the excited electron-hole pairs, but also utilize the ample redox capability of each semiconductor component in this system for the surface photocatalytic reaction. In this work, a TiO 2 –Au–BiOBr ternary Z-scheme photocatalyst was constructed, in which Au NPs were used as the electron mediator to join BiOBr nanosheets and TiO 2 nanofibers . The results showed that, under full spectrum irradiation, TiO 2 –Au–BiOBr nanofibers exhibited outstanding photocatalytic performance toward the degradation of Rhodamine B (RhB) with an excellent photodegradation efficiency of 99.91% within 30 min as well as good stability. The reaction mechanism of the TiO 2 –Au–BiOBr Z-scheme system was systemically studied by XPS , photoelectrochemical tests and free radical trapping experiments, etc. Moreover, the photocatalyst also exhibited excellent photocatalytic activity for degrading methyl orange and methylene blue.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2025
·
IF 3.3
Hanben Zhou,Run Liu
A composite was formed to improve the photo-generated carrier separation rate of semiconductor oxides synthesized by in-situ electrodeposition and calcination. ZnO/g-C3N4 was deposited on the surface of Au/FTO through simultaneous adsorbing during electrodeposition and calcination. Characterization showed the g-C3N4 layer was an ultrathin protective film above the surface of ZnO. The composite Au/ZnO/g-C3N4 had a photocurrent up to 0.24 mA/cm2 at 1.23V vs RHE, 70% higher than bare ZnO. In this structure, the holes of ZnO generated by lights can transfer to the g-C3N4 layer and electrons can transfer to the gold layer, accelerating charge transfer and reducing the accumulation of holes on the surface of ZnO, enhancing the photoresponse and stability. The separation of holes by g-C3N4 is a critical part of this structure.
研究领域:
材料科学
·
光电化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Yang Lu,Jiafeng Zhang,Wei Wang,Yizhuo Fan,Caixia Liu,Jingran Zhou,Dali Liu,Shengping Ruan
Two-dimensional metal sulfide semiconductor materials have received a lot of attention recently due to their large surface-to-volume ratio, outstanding chemical properties, and suitable band gap, and possess the potential in the application of gas sensors. In this work, SnS 2 nanosheets were synthesized by a simple hydrothermal method and successfully modified with Au, Pd, and Au-Pd nanoparticles on their surfaces using reducing agents for xylene detection. The experimental results show that the gas-sensitive performance of the sensor can be significantly improved by modifying Au-Pd nanoparticles on the surface of SnS 2 nanosheets , which can be attributed to the synergistic effect of the bimetal and the catalytic properties of bimetallic systems. The response of the prepared sensor is more than ten times higher than that of the pure material. In addition, the optimal operating temperature of the sensor modified by Au-Pd nanoparticles was also decreased compared to that of the sensor prepared by SnS 2 . The outstanding performance makes Au-Pd nanoparticles-modified SnS 2 gas sensor a great potential candidate for xylene detection.
研究领域:
材料科学
·
传感器技术
·
化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2013
·
IF 3.777
Yan Tong,Zhicheng Li,Xiaofeng Lu,Liu Yang,Weining Sun,Guangdi Nie,Zhaojie Wang,Ce Wang
An electrochemical method for the detection of dopamine based on a glass carbon electrode modified with electrospun CeO 2 /Au composite nanofibers was investigated in this article. The CeO 2 /Au composite nanofibers were prepared by the electrospinning technique and then annealed in air. The CeO 2 /Au composite nanofibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. Cyclic voltammetry (CV) showed that the electrospun CeO 2 /Au composite nanofibers modified carbon glass electrode exhibited an excellent electrocatalytic response to the dopamine (DA). The detection limit (S/N = 3) was as low as 0.056 μM and the sensitivity could reach 127 μA mM −1 cm −2 . All these demonstrated that the electrospun CeO 2 /Au composite nanofibers were good electrocatalyst for the oxidation of dopamine.
研究领域:
分析化学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子