Advanced Science
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2019
·Vol. 6
·期 12
·1900310
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IF 15.804
Lili Yang,Yusi Peng,Yong Yang,Jianjun Liu,Haoliang Huang,Bohan Yu,Jimin Zhao,Yalin Lu,Zhengren Huang,Zhiyuan Li,John R. Lombardi
Recent achievements in semiconductor surface-enhanced Raman scattering (SERS) substrates have greatly expanded the application of SERS technique in various fields. However, exploring novel ultra-sensitive semiconductor SERS materials is a high-priority task. Here, a new semiconductor SERS-active substrate, Ta 2 O 5 , is developed and an important strategy, the “coupled resonance” effect, is presented, to optimize the SERS performance of semiconductor materials by energy band engineering. The optimized Mo-doped Ta 2 O 5 substrate exhibits a remarkable SERS sensitivity with an enhancement factor of 2.2 × 10 7 and a very low detection limit of 9 × 10 −9 m for methyl violet (MV) molecules, demonstrating one of the highest sensitivities among those reported for semiconductor SERS substrates. This remarkable enhancement can be attributed to the synergistic resonance enhancement of three components under 532 nm laser excitation: i) MV molecular resonance, ii) photoinduced charge transfer resonance between MV molecules and Ta 2 O 5 nanorods, and iii) electromagnetic enhancement around the “gap” and “tip” of anisotropic Ta 2 O 5 nanorods. Furthermore, it is discovered that the concomitant photoinduced degradation of the probed molecules in the time-scale of SERS detection is a non-negligible factor that limits the SERS performance of semiconductors with photocatalytic activity.
研究领域:
材料科学
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光学
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分析化学
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DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 19
·11378-11389
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IF 10.7
Wanxing Zheng,Yufei Tang,Chaofeng Jia,Zhaowei Liu,Zhuangzhuang Zhang,Kang Zhao
Ultrasound is commonly employed as a source of mechanical energy in piezocatalysis, where it serves as an external excitation source inducing piezopotential that drives surface chemical reactions on the catalysts. The augmentation of mechanical energy generally amplifies the piezoelectric potential on the surface of the piezoelectric catalyst, thereby augmenting its piezoelectric catalytic activity. However, increasing the input of mechanical energy results in elevated equipment energy consumption, particularly for ultrasound generators. Therefore, it is imperative to develop a methodology capable of imparting significant mechanical energy to the piezoelectric catalyst while minimizing energy dissipation. In general, the resonance frequency is where the largest amplitude is accessible. Therefore, excitation of the matching piezocatalyst at this frequency should result in a higher level of piezocatalytic activity and an improvement in energy conversion efficiency. In this study, we proposed that the length of piezoelectric KNbO3 nanofibers is fixed to match the low-frequency ultrasound (LFUS) and calculated the length of the KNbO3 nanofibers at low-frequency resonance through simulation. The piezocatalytic activity of KNbO3 nanofibers at matched and unmatched natural and ultrasonic frequencies was investigated. Even at a reduced ultrasound power of 25 W, a notably high piezocatalytic activity was observed under the resonance, offering strong evidence for resonance-enhanced piezocatalysis. This work presents a fresh way for LFUS-activated piezocatalysis to achieve efficient degradation, which is of practical significance in energy-saving water treatment.
研究领域:
材料科学
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环境科学
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物理学
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DOI
高影响因子
Small
·
2018
·Vol. 14
·期 14
·1704079
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IF 9.598
Peng Miao,Jing-Kai Qin,Yunfeng Shen,Huimin Su,Junfeng Dai,Bo Song,Yunchen Du,Mengtao Sun,Wei Zhang,Hsing-Lin Wang,Cheng-Yan Xu,Ping Xu
2D transition metal dichalcogenides materials are explored as potential surface-enhanced Raman spectroscopy substrates. Herein, a systematic study of the Raman enhancement mechanism on distorted 1T (1T′) rhenium disulfide (ReS 2 ) nanosheets is demonstrated. Combined Raman and photoluminescence studies with the introduction of an Al 2 O 3 dielectric layer unambiguously reveal that Raman enhancement on ReS 2 materials is from a charge transfer process rather than from an energy transfer process, and Raman enhancement is inversely proportional while the photoluminescence quenching effect is proportional to the layer number (thickness) of ReS 2 nanosheets. On monolayer ReS 2 film, a strong resonance-enhanced Raman scattering effect dependent on the laser excitation energy is detected, and a detection limit as low as 10 −9 m can be reached from the studied dye molecules such as rhodamine 6G and methylene blue. Such a high enhancement factor achieved through enhanced charge interaction between target molecule and substrate suggests that with careful consideration of the layer-number-dependent feature and excitation-energy-related resonance effect, ReS 2 is a promising Raman enhancement platform for sensing applications.
研究领域:
材料科学
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光学
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纳米技术
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DOI
高影响因子
Analytical Methods
·
2016
·Vol. 8
·期 9
·2097-2105
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IF 1.915
Junrong Li,Liang Lv,Guannan Zhang,Xiaodong Zhou,Aiguo Shen,Jiming Hu
We herein present a simple and surfactant-free synthetic strategy for the preparation of core–shell Fructus Broussonetia-like Au@Ag@Pt nanoparticles (FBNPs) via a combination of galvanic replacement and reagent reduction, in which a chitosan (CS)-mediated epitaxial growth of Pt multi-branches occurs on cresyl violet labeled Au core–Ag shell nanoparticles (NPs) at room temperature. The as-prepared novel nanostructures exhibit an enzyme mimetic activity due to the formation of a Fructus Broussonetia-shaped Pt shell, the absence of surfactants and the positively charged CS molecules intertwined within the outermost Pt NPs. Relying on the high sensitivity of resonance-enhanced Raman scattering and the highly efficient intrinsic peroxidase-like activity of FBNPs, H2O2 was detected with a wide detection window from 10 pM to 100 μM when utilizing 3,3′,5,5′-tetramethylbenzidine (TMB) as the substrate. Based on the H2O2–TMB catalytic oxidation system a simple, sensitive, selective and universal platform has been extended for the detection of all peroxidase-related analytes. For example, glucose at a concentration range of 1 nM to 200 μM was detected in the presence of glucose oxidase with a limit of detection of 1 nM.
研究领域:
纳米材料
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生物分析化学
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医学诊断
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DOI
高影响因子
SENSORS
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2021
·Vol. 21
·期 9
·3238
·
IF 3.576
Jun Hu,Rui Chen,Zhen Xu,Maopeng Li,Yungui Ma,Yong He,Yande Liu
It is very important for human health to supervise the use of food additives, because excessive use of food additives will cause harm to the human body, especially lead to organ failures and even cancers. Therefore, it is important to realize high-sensibility detection of benzoic acid, a widely used food additive. Based on the theory of electromagnetism, this research attempts to design a terahertz-enhanced metamaterial resonator, using a metamaterial resonator to achieve enhanced detection of benzoic acid additives by using terahertz technology. The absorption peak of the metamaterial resonator is designed to be 1.95 THz, and the effectiveness of the metamaterial resonator is verified. Firstly, the original THz spectra of benzoic acid aqueous solution samples based on metamaterial are collected. Secondly, smoothing, multivariate scattering correction (MSC), and smoothing combined with first derivative (SG + 1 D) methods are used to preprocess the spectra to study the better spectral pretreatment methods. Then, Uninformative Variable Elimination (UVE) and Competitive Adaptive Reweighted Sampling (CARS) are used to explore the optimal terahertz band selection method. Finally, Partial Least Squares (PLS) and Least square support vector machine (LS-SVM) models are established, respectively, to realize the enhanced detection of benzoic acid additives. The LS-SVM model combined with CARS has the best effect, with the correlation coefficient of prediction set (Rp) is 0.9953, the root mean square error of prediction set (RMSEP) is 7.3 × 10−6, and the limit of detection (LOD) is 2.3610 × 10−5g/mL. The research results lay a foundation for THz spectral analysis of benzoic acid additives, so that THz technology-based detection of benzoic acid additives in food can reach requirements stipulated in the national standard. This research is of great significance for promoting the detection and analysis of trace additives in food, whose results can also serve as a reference to the detection of antibiotic residues, banned additives, and other trace substances.Keywords:THz detection technology;metamaterials;trace additives;resonance enhancement;LS-SVM
研究领域:
食品安全检测
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生物物理学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2023
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IF 3.8
Shuxian Li,Yan Zhao,Fuqiang Hu,Yuechun Jiao,Jianming Zhao,Changyong Li
Ethoxy-substituted benzene has several stable conformations as the single bond in the ethoxy group is capable of internal rotation. Ethoxybenzonitrile may has more conformers due to different orientations of ethoxy with respect to the CN group. In this paper, the potential energy surface (PES) of 2-ethoxybenzonitrile in the ground state was calculated at the level of B3LYP/cc-pvdz, and five different molecular conformers were found on the PES. Only the most stable conformer I (trans) was observed in the supersonic molecular beam experiments. The resonance enhanced multiphoton ionization (REMPI) and mass analyzed threshold ionization (MATI) spectra of 2-ethoxybenzonitrile were measured and Franck-Condon simulations were performed, and the theoretical results are in good agreement with the experimental measurements. The similar molecular structures in S 0 , S 1 , and D 0 states imply the large Franck-Condon factors. The vibronic structures in S 1 and D 0 states were analyzed in detail and the vibronic features were assigned. The MATI spectra follow well the propensity rule Δν = 0, indicating that the molecular structures of the cationic and excited states are similar. Most of the observed vibrations are associated with the ring in-plane distortion. The band origin of the S 1 ←S 0 transition and the accurate adiabatic ionization energy of 2-ethoxybenzonitrile are determined for the first time to be 34 092 ± 2 and 69 796 ± 5 cm −1 , respectively.
研究领域:
物理化学
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分子光谱学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2022
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IF 9.221
Yu Sun,Jinyong Hu,Yong Zhang
Transition metal dichalcogenides (TMDs) have been received widespread attention for NO 2 detection at room temperature . However, the TMDs-based gas sensors usually possess inferior response capability and suffer from humidity interference due to lack of sufficient reaction activation energy , which seems tough to achieve the detection of ppb-level gases and hinder the practical applications. Herein, we propose a visible light-assisted-type gas sensor based on Au-decorated WS 2 , endowing high-performance detection of NO 2 at room temperature. Benefited from the localized surface plasmon resonance (LSPR) enhancement effect induced by the modified Au nanoparticles (NPs), the visible light-assisted Au/WS 2 gas sensor can implement the detection of NO 2 gas as low as 20 ppb. Moreover, the maximum drift of the sensor response value is only 3% in the range of 10%−90% RH, indicating the stabilized anti-humidity ability. The effective regulation of transmission channel by the modified noble metal and the enhancement of visible light absorption of WS 2 through taking full advantage of the LSPR effect are the main reasons for realizing low concentration detection and improving the anti-humidity ability. Therefore, the visible light-assisted gas detection mode can serve as a proof-of-concept to provide an effective approach for the detection of trace gases at room temperature.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Laser & Photonics Reviews
·
2025
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IF 10
Qiang Niu,Jiarui Hu,Han Hao,Rong Zhao,Guling Zhang,Jinfeng Zhu,Yuping Yang
Enhancing the interaction between light and matter, especially at the terahertz band, is pivotal for achieving ultra-broadband trace molecular fingerprint detection. Here, an efficient scheme featuring multiple Fabry–Pérot modes with equal intervals and uniform intensity is presented to implement a resonance interaction enhancement of molecular fingerprints with long-awaited precision and flexibility. This technique constructs uniform resonant probes across the entire spectral range to reveal molecular coupling effects via frequency-selective amplitude attenuation, enabling both qualitative and quantitative detection of L-tyrosine with a detection limit of 0.11 µg mm −2 . This is an inaugural experimental achievement of quantitative THz trace fingerprint detection with dual capabilities of achieving ultra-broadband and high-efficiency. Significantly, the technology enables direct identification of molecular absorption signatures from the transmitted multiple Fabry–Pérot modes using wavelet denoising algorithms, eliminating cumbersome data postprocessing and redundant testing procedures. This advancement heralds a new, accessible era in terahertz fingerprint spectroscopy.
研究领域:
生物物理化学
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分子光谱学
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生物医学工程
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转化医学
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分析化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）