Journal of Ocean University of China
·
2019
·Vol. 18
·期 6
·1523-1531
·
IF 0.699
Shi Xiaofeng,Yan Xia,Zhang Xinmin,Ma Lizhen,Zhang Xu,Wang Chunyan,Ma Jun
Sensitivity is crucially important for surface-enhanced Raman spectroscopy (SERS) application to detect trace-level polycyclic aromatic hydrocarbons (PAHs) in the seawater. In this study, a high sensitivity three-dimensional (3-D) SERS substrate composed with syringe filter, glycidyl methacrylate-ethylene dimethacrylate (GMA-EDMA) porous material and optimal parameters (57 nm, pH 13) gold nanoparticles (AuNPs) was developed for the detection of PAHs in water. The enhancement effect and repeatability of this 3-D substrate were also explored. The Raman intensity of pyrene using 3-D SERS substrate is about 8 times higher than that of substrate only using pH 13 gold colloid solution and about 12 times higher than that of substrate using natural AuNPs and GMA-EDMA porous material, which means both the pH 13 AuNPs and the GMA-EDMA porous material are important factors for the sensitivity of this 3-D SERS substrate. Good repeatability of this optimal 3-D substrate was obtained. The relative standard deviation (RSD) is less than 8.66% on the same substrate and less than 3.69% on other different substrates. Four kinds of PAHs, i.e. , phenanthrene, pyrene, benzo(a)pyrene, benzo(k)fluoranthene and their mixture, were detected at the different concentrations. Their limits of detection (LODs) are 8.3×10 −10 (phenanthrene), 2.1×10 −10 (pyrene), 3.8×10 −10 (benzo(a)pyrene) and 1.7×10 −10 mol L −1 (benzo (k)fluoranthene), respectively. In addition, these four PAHs were also detected by fluorescence spectroscopy to evaluate the sensitivity of SERS technology using this optimal 3-D SERS substrate. The results showed that the sensitivity of SERS based on the 3-D SERS substrate even using the portable Raman system was closed to that of fluorescence spectroscopy. Therefore, the SERS technology using this optimal 3-D substrate is expected to be an in-situ method for the detection of environmental PAHs.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Qian Zhang,Xiang-Dong Wang,Ting Tian,Li-Qiang Chu
Surface-enhanced Raman scattering (SERS) sensors have been extensively studied for ultrasensitive detection of diverse chemical or biological analytes. Facile fabrication of highly sensitive SERS substrates is believed to be of crucial importance in these analytical applications. In this regard, the preparation of 3-dimensional (3D) SERS substrates are explored via the incorporation of multilayered silver nanoparticles (AgNPs) into poly (oligo(ethylene glycol) methacrylate) (POEGMA) brushes by repeating the immersion-rinsing-drying steps for different lengths of time (i.e., the so-called in-stacking method). The POEGMA brushes of different chain lengths are synthesized by surface-initiated atom transfer radical polymerization (ATRP) with various reaction time. The resulting POEGMA/AgNP nanocomposites are characterized by FE-SEM, UV–vis and Raman spectroscopy. FE-SEM and UV–vis results indicate that the AgNPs are successfully incorporated into the POEGMA brushes with a 3D configuration. The nanocomposite films are employed as SERS substrates for the detection of a Raman reporter molecule (i.e., 4-aminothiophenol), giving rise to an enhancement factor of up to 1.29 × 10 7 and also having relatively good uniformity and reproducibility. The obtained 3D SERS substrates are also used for the detection of a typical gram-positive bacterium, Staphylococcus aureus . The limit of detection is found to be as low as ca. 8 CFU/mL.
研究领域:
分析化学
·
材料科学
·
生物医学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2019
·Vol. 30
·期 34
·345604
·
IF 3.399
Mengmeng Gao,Xiang Lin,Zhenghua Li,Xiaoxia Wang,Yebing Qiao,Haiyan Zhao,Jing Zhang,Li Wang
A highly sensitive and uniform three-dimensional (3D) surface-enhanced Raman spectroscopy (SERS) substrate has been fabricated by in situ ultraviolet ozone cleaning and layer-by-layer self-assembly. The SERS properties and the structural changes of the substrates were systematically studied by adjusting the cleaning time upon the in situ and post cleaning strategy. Under the optimal cleaning condition, the cleaning technology could give rise to clean and optimal surfaces for SERS analysis, thus obtaining efficient plasmonic films populated with a large number of homogeneous 'hot-spots'. Then with the optimal monolayer film, the SERS performance derived from plasmon coupling in multilayers of the Au@Ag nanocubes substrates was explored. It demonstrated that the plasmon coupling between layers (out-of-plane) contributed much to the SERS intensity, leading a more superior SERS enhancement from the 3D SERS substrates than that from the conventional two-dimensional SERS substrates. Also the in situ cleaning 3D SERS substrates displayed a nice uniformity and excellent time stability. With this method, the optimized substrates were further used to detect prohibited pigments in drink with an excellent linear relationship between characteristic peak intensity and analytes concentration over wide concentration ranges. Our experimental results clearly show that the in situ cleaning 3D SERS substrates provide an ideal candidate for SERS applications in food safety.
研究领域:
分析化学
·
食品安全检测
·
纳米材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2021
·Vol. 34
·期 1
·2106897
·
IF 30.849
Jiahui Zhou,Man Xie,Feng Wu,Yang Mei,Yutong Hao,Li Li,Renjie Chen
A 3D host can effectively mitigate the dendritic growth of a zinc (Zn)-metal anode. However, the increased electrode/electrolyte reaction area using the 3D substrate accelerates the passivation and corrosion at the anode interface, ultimately degrading the electrochemical performance. Here, an oriented freezing process is used to create a flexible MXene/graphene scaffold. Based on the abundant zincophilic traits and micropores in the structure, Zn is densely encapsulated inside the host by the electrodeposition process. During cycling, the composite anode endows an in situ solid electrolyte interface with zinc fluoride at the electrode/electrolyte interface due to inherent fluorine terminations in MXene, efficiently inhibiting the dendritic growth. Furthermore, the design wherein bulk Zn is distributed in a 3D microscale manner suppresses hydrogen evolution reactions (3.8 mmol h −1 cm −2 ) and passivation, through in/ex situ tests. As a result, in a symmetrical cell test, the electrode has a long-cycling life of over 1000 h at 10 mA cm −2 . After continuous single folding followed by double folding, a quasi-solid-state foldable cell with the composite anode and a LiMn 2 O 4 cathode (60% depth of discharge) maintains high-capacity retention of over 91%. This research presents a revolutionary encapsulating idea for aqueous Zn-ion batteries, as well as foldable investigation.
研究领域:
材料科学
·
电化学
·
储能技术
✓ 已验证
DOI
高影响因子
Journal of Nanotechnology
·
2018
·
IF 0
Xiaodong Wang,Xiulan Cheng,Xufeng Yu,Xueling Quan
A 3D surface-enhanced Raman scattering (SERS) substrate based on titanium oxide nanorods (TiOx-NRs) coated with gold nanoparticles (Au-NPs) was fabricated by a simple hydrothermal, no-template process. The nanostructure of TiOx-NRs influenced by the concentrations of hydrochloric (HCl) acid and sodium chloride (NaCl) was studied in detail. The substrate showed the strongest Raman enhancement, when the diameters of Au-NPs were around 40 nm and the gaps of Au-NPs were in the range of 5 nm to 10 nm. The surface electric field of our substrate was examined by finite-different time-domain (FDTD) solutions. Rhodamine 6G (R6G) was chosen as the probe molecule to study the SERS performance of the substrates. The Raman signal of 10−10 M R6G was detected clearly by the substrate with the enhancement factor of 2.64 × 108. All relative standard deviation (RSD) values of the major peaks for R6G were within the scope of 10.4% to 16.7%. The substrate could work efficiently even after immersed in water for one month.
研究领域:
材料科学
·
纳米技术
·
光谱学
✓ 已验证
产品关联
DOI
Frontiers in Chemistry
·
2022
·
IF 5.545
Zhai Haichao,Zhu Chuhong,Wang Xiujuan,Yuan Yupeng,Tang Haibin
Three-dimensional surface-enhanced Raman scattering (SERS) substrates usually provide more hot spots in the excitation light beam and higher sensitivity when compared with the two-dimensional counterpart. Here a simple approach is presented for the fabrication of arrays of Ag-nanoparticles decorated TiO2 nanotubes. Arrays of ZnO nanorods were fabricated in advance by a hydrothermal method. Then TiO2 nanotube arrays were achieved by immersing the arrays of ZnO nanorods in an aqueous solution of (NH4)2TiF6 for 1.5 h. Vertically aligned TiO2 nanotube arrays were modified with dense Ag nanoparticles by Ag mirror reaction. High density of Ag nanoparticles decorated on the fabricated TiO2 nanotubes provide plenty of hotspots for Raman enhancement. In addition, the fabricated array of Ag nanoparticles modified TiO2 nanotubes can serve as a reusable SERS substrate because of the photocatalytic activity of the TiO2 nanotubes. The SERS substrate adsorbed with analyte molecules can realize self-cleaning in deionized water after UV irradiation for 2.5 h. The sensitivity of the fabricated SERS substrate was investigated by the detection of organic dye molecules. The detectable concentration limits of rhodamine 6G (R6G), malachite green (MG) and methylene blue (MB) were found to be 10−12 M, 10−9 M and 10−8 M, respectively. The enhancement factor (EF) of the three-dimensional SERS substrate was estimated to be as high as ∼1.4×108. Therefore, the prepared Ag nanoparticles modified TiO2 nanotube arrays have promising potentials to be applied to rapid and trace SERS detection of organic chemicals.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
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