SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2022
·
IF 4.831
Jia Li,Huizhu Zhang,Dongxue Yu,Weie Wang,Wei Song,Libin Yang,Xin Jiang,Bing Zhao
Considering the variable valence characteristics of rare earth elements, they can be in a variety of valence forms coexistence. Doping of rare earth element with different valence states may produce different energy levels to tune the semiconductor energy band structure. We utilize rare earth element Ce doping TiO 2 for the development of high-performance semiconductor surface-enhanced Raman scattering (SERS) substrates based on an energy-level tuning strategy. Ce doping not only forms multiple energy levels including Ce 3+ and Ce 4+ metal doping energy levels in the bandgap of TiO 2 , but also enriches the surface state level of TiO 2 itself, which together promote the separation of photogenerated carriers and improve charge transfer efficiency between substrates and absorbed molecules. This endows TiO 2 semiconductor substrate with a higher SERS enhancement factor, which can reach 2.2 × 10 6 . The detectable concentration of methylene blue can be as low as 10 −10 mol/L. Moreover, the semiconductor substrate exhibits excellent uniformity and stability. This study not only provides a new strategy to develop excellent semiconductor SERS substrate with multiple energy levels, but also lays the foundation for promising practical application of semiconductor substrate.
研究领域:
材料科学
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表面增强拉曼散射
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Xiaoxu Zhang,Chengxu Song,Shilun Li,Liang Chen,Jing Xu,Wei Liu,Shangshen Feng
The effective regulation of the absorption properties of Au nanosphere arrays, as well as effective enhancement of its SERS performance, are of great significance for its applications in the field of optical sensing. In this paper, the polyol synthesis method was used to fabricate monolayer and bilayer periodic Au nanosphere arrays, onto which monolayer graphene was coated, and the optical properties of the obtained composite structures were investigated. The results showed that the coverage of graphene enhances the absorption peak intensities of the monolayer and bilayer Au nanoarrays by up to 32.92%, and the resonance peaks were red-shifted by up to 17 nm. The Raman signals of graphene-covered monolayer and bilayer Au nanosphere composite arrays are 180 and 280 times stronger than that of pristine graphene, due to the combination of chemical enhancement and electromagnetic enhancement. And the detection sensitivity of R6G molecules by graphene-bilayer Au nanosphere composite arrays is 10 −6 M. In addition, the staggered stacking of bilayer Au nanosphere arrays can provide more plasmonic hotspots, resulting in higher Raman intensity of the substrate. These results will pave the way for the fabrication of highly efficient SERS substrates by providing various promising candidates.
研究领域:
材料科学
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光学传感
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Jia Li,Yimin Tang,Xiuwen Wang,Wei Kan,Libin Yang,Xin Jiang,Yukihiro Ozaki,Xiaoxia Han,Bing Zhao
Surface oxygen vacancy defects and energy band defects can be synchronously regulated to accelerate the charge transfer in a semiconductor–molecule system for boosting the surface-enhanced Raman scattering (SERS) performance of a semiconductor. Herein, alkaline earth metal Sr with a low electronegativity and a large atomic radius was selected as a dopant to prepare a Sr-doped TiO2 (SrnTiO2) SERS substrate, in which a simple Sr doping achieves a synchronous regulation of double defects (i.e., surface oxygen vacancy defect and energy level defect of Ti) in TiO2. Abundant surface oxygen vacancies and defect energy levels of Ti are jointly responsible for the greatly enhanced SERS performance of the substrate. On the optimal substrate Sr0.0100TiO2, the minimum detection limit of a nonresonance molecule, 4-mercaptobenzoic acid, can reach 1 × 10–9 M, and the enhancement factor is as high as 9.3 × 106. To the best of our knowledge, this is the highest SERS activity among the reported semiconducting substrates, even comparable to those of precious metals. Moreover, the SrnTiO2 substrate shows an excellent spectral reproducibility and ultrahigh stability, which can withstand the corrosions of strong acid and alkali and even can resist the oxidation of high temperatures for SERS detection.
研究领域:
材料科学
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化学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2025
·
IF 5.5
Zhaoguo Wu,Xuezhi Zhou,Aiwu Zhao,Jin Wang
A combination of endoskeleton and exoskeleton in a dual shell has been considered for simultaneously improving the core–satellite binding efficiency and stability. A two-step preassembling-postgrowth approach has been considered for fabricating dual stimulus-responsive core–shell–satellite–shell (CSSS) nanocomposites. A CSSS therapeutic nanosystem has been designed for controllable release of the drug and in situ monitoring of chemotherapy via a dual stimulus-responsive mode. Incorporation of bifunctional SH-PNIPAM-COOH (TPNIC) in the nanocomposites plays a dual role in cross-linking of core–satellites and stimulus-responsive Raman enhancement. On the one hand, TPNIC in swelling status can act as a cross-linker for assembling Au satellites on the PFe3O4 (PEI-functionalized Fe3O4) core. On the other hand, TPNIC can adjust the assembling status of Au satellites via alteration of temperature; moreover, it induces optical hot-spot generation for giving a coupling plasmonic effect to produce a much stronger SERS performance than simple assembling. Thus, collapse of the TPNIC layer in the nanocomposites above the lower critical solution temperature (LCST) can be adopted for in situ enhanced monitoring chemotherapeutics of releasing the drug doxorubicin in a tumor microenvironment (TME). The dual stimulus-responsive therapeutic nanosystem can contribute to delivering the anticancer drug for efficiently penetrating the cell membrane and retarding release of the anticancer drug in TME. The obvious advantages of the therapeutic nanosystem are its facile magnetic recycling and regeneration so as to realize a sustainable chemotherapy of the tumor.
研究领域:
生物医学工程
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纳米医学
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肿瘤学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2017
·Vol. 53
·期 5
·3443-3454
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IF 2.599
Liu Jiao,Jiang Peng-peng,He Chun,Jiang Xiao-hong,Lu Lu-de
Here, novel and stable core–shell silver–carbon nanocomposites (Ag@CSs) were obtained using glucose as the carbon source and stabilizer, silver nitrate as the silver source, and trioctylamine (TOA) as the soft template and extractant. It is worth mentioning that the shape of the silver core shows the hexagon shape, and we consider that TOA and glucose selectively adsorb the Ag (111) crystal face resulting in this growth pattern of the silver core. Owing to the enhanced local field effect around their sharp corners and edges, such structure exhibits superior properties for the surface-enhanced Raman scattering (SERS) enhancement. The hydrothermal carbon shell not only effectively avoids the agglomeration of Ag nanoparticles core, but also serves as a protective layer of the SERS active nanostructure during the whole course of the experiment. In addition, the thickness of the loose shell was significantly reduced after the product was stored in ethanol solution for a period of time. It is found that dropped cast probe molecules onto Ag@CSs have a lower SERS activity, while that immersed in the probe molecular solution for a period of time have a higher SERS activity, indicating that the detection of the probe molecules using this Ag@CSs substrate may require an interactive process. The results show that the as-obtained Ag@CSs hold tremendous potential for SERS applications for its long-term stability and superior SERS performance.
研究领域:
材料科学
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纳米技术
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光谱学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Yu Han,Si-Rong Wu,Xiang-Dong Tian,Yun Zhang
Three-dimensional (3D) plasmonic nanostructures are emerging as excellent surface-enhanced Raman spectroscopy (SERS) substrates for chemical and biomedical applications. However, the correlation of 3D (including both in-plane and out-of-plane) plasmonic coupling with the SERS properties to deepen the understanding of 3D SERS substrates remains a challenge. Here, we perform correlation studies of 3D plasmonic coupling and SERS properties of the 3D hierarchical SERS substrates by tuning the multiscale structural elements. The effects of zero-dimensional (0D; the size of the building blocks), one-dimensional (1D; the thickness of the 3D substrates), and two-dimensional (2D; the composition of individual monolayers) structural elements on 3D plasmonic coupling are studied by performing UV–vis–near-infrared (NIR) spectroscopy and measuring SERS performance. It shows that both the extinction spectra and SERS enhancement are tuned at the 3D structural level. It is demonstrated that the plasmonic resonance wavelength (PRW) stemming from the 3D plasmonic coupling correlates with the SERS averaged surface enhancement factor (ASEF) and is improved by more than tenfold at the optimum 3D nanostructure. The optimized substrate is used to quantitatively analyze two small biological molecules. Moreover, as a proof-of-concept study, the substrate is first applied to differentiate between living liver normal and cancer cells with a high prediction accuracy through the spectral features of the cell membranes and the metabolites secreted outside the cells. We expect that the tuning of plasmonic coupling at the 3D level can open up new routes to design high-performance SERS substrates for wide applications.
研究领域:
生物医学工程
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光谱学
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癌症研究
✓ 已验证
DOI
高影响因子
OPTICS EXPRESS
·
2022
·Vol. 30
·期 25
·44827-44836
·
IF 3.833
Lei Zha,Xiaohui Fang,Yu Han,Xinping Zhang
Three-dimensional surface-enhanced Raman scattering (SERS) platform based on microstructure fibers has many advantages for rapid liquid detection due to its microfluidic channels and light guidance. The fiber mode field distribution determines the light-analyte interaction strength but has rarely been studied in SERS applications. In this paper, we numerically and experimentally investigate the mode field distribution in suspended-core fibers decorated with gold nanoparticles. The interaction between the core mode and surface mode is controlled by changing the density of gold nanoparticles on the inner surface. The avoided crossing wavelength shifts linearly to red with the decrease of the nanoparticle spacing. With an optimized nanoparticle spacing of 20 nm, the avoided crossing occurs near the laser wavelength of 633 nm, which greatly increases the power ratio in the liquid channels and hence improves the SERS performance. The detection limit for crystal violet was 10−9 M, and the enhancement factor was 108. The avoided crossing mechanism can be applied to all fiber SERS probes for sensitivity improvement.
研究领域:
光学
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纳米技术
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分析化学
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光子学
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产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2019
·Vol. 21
·期 24
·3709-3720
·
IF 3.382
Shanshan Li,Qi Wang,Xinyu Song,Yuxiang Bu
Semiconductor-based materials as SERS-active substrates have gained significant attention because of their superior properties. However, to date, only few studies have been reported on the SERS performance of substrates fabricated using CdS-based composites. In this study, hollow sphere-like Ag/CdS nanocomposites (NCs) with multi-hot spots were successfully synthesized via a room-temperature solution route without the addition of surfactant. Especially, note that in our strategy, the cadmium ions in an aqueous solution originating from the self-template core dissolved with acid were retrieved and recycled via a simple approach, avoiding the wastage of resources and environmental problems. Moreover, a strong electromagnetic enhancement between two neighboring Ag nanoparticles (NPs) on the CdS sphere-like surface could be achieved by conveniently adjusting the amount of the AgNO3 reagent. Note that the as-prepared substrate with low loading of Ag presented superior SERS performance with the ultralow limit of detection of 10−12 mol L−1 for R6G and CV, much higher than that of many recently reported composite substrates. These significantly enhanced SERS effects are attributed to the combination of several contributions, including plasmonic coupling between Ag NPs, synergistic charge-transfer resonances in the Ag/CdS/dye molecule system, and cadmium defect-induced electrostatic forces. As a consequence, the present study not only develops a convenient, environmentally friendly approach for the fabrication of noble/CdS composites but also indicates the promising potential application of these composites as ideal SERS substrates in the detection of organic pollutants.
研究领域:
材料科学
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纳米技术
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表面增强拉曼光谱 (SERS)
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2023
·
IF 6.2
Yaoyu Tan,Mengyao Qi,Huan Jiang,Baihui Wang,Xia Zhang
The level of uric acid is crucial to human health. Octahedral oxygen vacancy MnCo 2 O 4 /Ag (V O -MnCo 2 O 4 /Ag) nanozyme was successfully prepared by simple hydrothermal, calcination and self-reduction methods. V O -MnCo 2 O 4 /Ag nanozyme is rich in Mn 2+ /Mn 3+ and C O 2+ /C O 3+ redox electron pairs, large specific surface area and oxygen vacancies. V O -MnCo 2 O 4 /Ag nanozyme showed high uricase-like activity and peroxidase-like activity. At the same time, the SERS signal of the detected molecule could be significantly enhanced after the catalytic reaction of the V O -MnCo 2 O 4 /Ag nanozyme. The K m values of V O -MnCo 2 O 4 /Ag nanozyme for H 2 O 2 and TMB were 0.04 mM and 0.027 mM respectively. Based on the uric acid oxidase-like and peroxidase-like activities of V O -MnCo 2 O 4 /Ag, we developed a label-free, sensitive, and reliable SERS uric acid detection system. The detection linear range of uric acid is 0.01 μM–1000 μM and the detection of limit is 7.8 × 10 −9 M. The results show that the sensing system has good accuracy, sensitivity, selectivity , and stability. It can be applied to the determination of samples under different conditions. This study provides profound insights into the design of enzyme-like activity regulation and SERS properties regulation of nanozymes, provides guidance for the study of reaction kinetics and catalytic mechanism of nanozymes, and has broad application prospects in the field of nanozymes and SERS sensing analysis.
研究领域:
纳米技术
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分析化学
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生物化学
·
材料科学
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医学诊断
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）