LANGMUIR
·
2025
·
IF 3.9
Yuqing Li,Can Liu,Xiaocong Tang,Bohao Liu,Wei Zhao,Yong Zhang
Metal nanoparticle surface modification is a simple and efficient method to realize highly sensitive detection for chemiresistive gas sensors. Although a few theoretical explanations for the complicated matching relationship in the sensing system constructed from the modified metal, semiconductor material, and target gas have been proposed, there are no corresponding specific evaluation parameters based on the metal sensitization mechanism, which are crucial for the guidance of high-performance sensing materials design. Herein, taking MnO2-based chemiresistive gas sensors as examples, the improvement effect of the metal nanoparticles modification on the gas-sensing properties of MnO2-based chemiresistive sensors toward HCHO and NH3 is investigated. Combined with the first-principle calculations based on density functional theory (DFT), a novel resonant coupling model based on the impurity energy levels, originating from charge transfer between target gas and metal, is first proposed to reveal the sensitization mechanism that the coupling strength between metal and target gas determines the carrier concentration of MOS. Coupling strength is closely positive correlated with the response, which provides an effective parameter to semiquantitatively describe the sensitization effect of metal nanoparticles on target gas. Our work establishes a model that clarifies the matching correlation in the sensing system and excavates new road to further comprehend the metal sensitization mechanism, which will provide an effective theoretical guide for the design of high-performance gas-sensing materials.
研究领域:
材料科学
·
化学传感器
✓ 已验证
DOI
PubMed
高影响因子
ACS Nano
·
2020
·
IF 14.588
Yinzhu Jiang,Hao Wang,Shiya Wen,Huanjun Chen,Shaozhi Deng
Recently, resonance coupling between plasmonic nanocavity and two-dimensional semiconductors has attracted considerable attention. Most of the previous studies have focused on demonstrating this effect with light scattering or reflection spectroscopy, while the photoluminescence (PL) spectrum can help ascertain the underlying physics. Here, we report on the light-emitting characteristics of a monolayer WS2 flake coupled with a plasmonic gold nanorod. We construct a heterostructure by integrating an individual gold nanorod on top of a small piece of monolayer WS2, where the WS2 area is determined by the projected area of the nanorod. In such a heterostructure, the background PL from the uncoupled WS2 can be suppressed, which allows us to characterize the resonance coupling effect using correlated single-particle dark-field (DF) scattering and PL spectroscopies. Distinct mode splitting and anticrossing dispersion are observed in the scattering spectra, which originate from the resonance coupling between the excitons in the WS2 and plasmon resonance in the gold nanorod. In addition, a 1187-fold enhancement is obtained for the light emitted from the heterostructure relative to that of the pristine monolayer WS2. The emission spectra are broadened with mode-splitting features at room temperature, which can be further decomposed into two resonance modes using a coupled mode analysis. Moreover, two PL modes are polarized along the longitudinal axis of the gold nanorod. These findings show the potential of the designed individual gold nanorod–monolayer WS2 heterostructure as a platform for studying the resonance coupling effect between plasmon resonance and two-dimensional excitons.
研究领域:
光学
·
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2019
·
IF 6.35
Yu Cao,Pei Liang,Qianmin Dong,Dan Wang,De Zhang,Lisha Tang,Le Wang,Shangzhong Jin,Dejiang Ni,Zhi Yu
Recently, more and more attention has been given to a semiconductor oxide-based surface-enhanced Raman spectroscopy substrate for its great stability and biocompatibility. However, its poor SERS sensitivity limits the applications of semiconductor oxide SERS substrates. In this paper, we provide a facile reduction method to modulate oxygen vacancy concentrations in oxide SERS substrates. Using MoO2 as an example, the resonance coupling as well as charge transfer between the semiconductor oxide SERS substrate and the target molecules were promoted for the reason of artificial oxygen vacancy embodied in the Raman signals being improved. By using the TEM, SEM, and XPS measurements, we confirmed that we successfully prepared defective MoO2–x with a polycrystalline surface. MoO2–x modulated oxygen vacancy treated with 6 wt % Li shows a very high detection sensitivity of 10–8 M (4.79 ug/L) for R6G, and the intensity of the Raman signal was highly enhanced. Because of the existence of defective energy levels, resonance coupling, as well as charge transfer between semiconductor and molecules, was obviously promoted. More importantly, the method of modulating oxygen vacancy can be widely used in semiconductor oxide materials for its chemical enhancement capacity can be promoted by artificial oxygen vacancy.
研究领域:
材料科学
·
光谱学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Wei-Yu Jia,Kai-Xin Xie,Rui-Ping Huo,Xiu-Li Song
Plasmonic regulation introduced by metallic nanoparticles is a useful method to improve the detection performance of plasmon-based systems. Herein, we observed a unique enhancement of surface plasmon-coupled emission (SPCE) using plate-shaped plasmonic nanostructures. By assembling Au nanoplates (Au NPLs) via electrostatic adsorption between the Au nanofilm and the quantum dot (QD) layer (630 nm), the fluorescence signal of SPCE was enhanced 90 times more than that of normal SPCE after the conditions were optimized. This enhancement was mainly induced by the intense localized electromagnetic field at the tip of Au NPLs and a novel plasmonic distribution around the “hot-spot” structure between the nanoparticle and Au nanofilm. These effectively mitigated the inherent signal quenching of SPCE and enhanced the emission signal of ultrathin samples on the surface of the NPL-modified Au nanofilm structure. This strategy can be used to improve the detection sensitivity and information integrity of SPCE-based biosensing and bioimaging systems containing ultrathin luminous layers. The different enhancement efficiencies for multiwavelengths were successfully obtained through various emission angles in light of the wavelength resolution of SPCE, thus verifying the existence and importance of energy-matching coupling, and the emission for the fluorophore with low excitation efficiency could also be detected. Benefiting from this, the Au NPL-modulated SPCE system could be a candidate for simultaneous multiwavelength enhancement and high-throughput detection in multicomponent analysis.
研究领域:
纳米生物学
·
光学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
IEEE SENSORS JOURNAL
·
2024
·
IF 4.3
Yumei Zhang,Liyun Ding,Shiyuan Wang,Xingdong Jiang,Fei Ma,Jue Zhao,Wenbo Meng,Long Gao
An enhanced resonance coupling of gold film-gold nanorods (GNRs) based optical fiber acetylcholine (Ach) biosensor was fabricated with increased sensitivity for refractive index (RI) sensing. Gold film with a thickness of about 50 nm is sputtered on the surface of the optical fiber by the magnetron sputtering, and then the GNRs synthesized by seed-mediated were immobilized on the surface of the gold film by using 1,6-hexodithiol as a crosslinker via cross-link method. The RI sensitivities (SRI) improvement rate of the sensors was 24.09% higher than that of the sensor without GNRs functionalization. Acetylcholinesterase (AchE), as the specific recognition substance of the biosensor, was immobilized on the surface of GNRs by the chemical crosslinking method to prepare optical fiber sensing probes. Under the optimum preparation conditions of the optical fiber sensing probe, the wavelength shift of the surface Plasmon resonance (SPR) peak has a good linear relationship with the concentration of Ach (CAch) in the range of 0.5– $5 \mu \text{g}$ /mL with the sensitivity of 0.4912 nm/( $\mu \text{g}$ /mL) and limit of detection (LOD) was $0.45 \mu \text{g}$ /mL. In addition, the optical fiber biosensor has good stability and selectivity, which makes it have broad application prospects in the early diagnosis of degenerative disease.
研究领域:
生物医学工程
·
传感技术
·
分子诊断
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Materials
·
2021
·
IF 3.515
Wen Shiya,Deng Shiyu,Chen Kun,Chen Huanjun,Deng Shaozhi
Resonance coupling between plasmonic resonances in metallic nanostructures and excitons in two-dimensional (2D) semiconductors has attracted much recent attention. The 2D semiconductor excitons are sensitive to external stimulus, enabling active tuning on the resonance couplings by physical, such as applying electrostatic gating, thermal scanning, etc., or chemical approaches. Among the others, chemical tuning approach has the advantage of facile implementation, high efficiency, and being capable of large-area tuning. Here, we report on chemical tuning of resonance coupling in heterostructures consisted of individual gold nanorods integrated with monolayer WS2. We showed that by incubating the heterostructures into a bis (trifluoro-methane) sulfonimide (TFSI) solution, the exciton transition strength of the WS2 will be enhanced significantly. As a result, the resonance coupling in the heterostructures evolved from a weak coupling regime to a strong coupling one, with the mode splitting energy increases from 94.96 to 105.32 meV. These findings highlight the potential of chemical treatment as an efficient technique for tailoring the interactions between plasmonic nanostructures and 2D semiconductors.
研究领域:
材料科学
·
纳米技术
·
光学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2023
·Vol. 15
·期 25
·10826-10833
·
IF 6.7
Huimin Wang,Tao Wang,Simei Zhong,Jinyan Zhang,Ruoqin Yan,Peng Xu,Yu-hui Zhang,Xinzhao Yue,Lu Wang,Yuandong Wang,Xuyang Yuan,Jinwei Zeng,Jian Wang
Gold nanoparticles (AuNPs) can be used to improve the performance of propagating surface plasmon resonance (PSPR) refractive index sensors. The resonant coupling effect between PSPR and localized surface plasmon resonance (LSPR) supported by AuNPs on sensitivity remains to be elucidated in terms of evanescent field intensity and distribution. In this study, we directly compare the sensitivity of the PSPR sensor and the resonant coupling mode between the PSPR and LSPR sensors in the wavelength scanning mode. The sensitivity of PSPR can be significantly improved in the near-infrared region excitation wavelength. 1,6-Hexanedithiol was used to achieve a AuNP modified gold film (GF-AuNP). The PSPR excited by the prism coupling mechanism can effectively stimulate LSPR supported by AuNPs in the GF-AuNP, and then resonant coupling is generated. Compared with PSPR, the resonant coupling mode shows a decrease in penetration depth by 28 times and an increase in the surface electric field intensity by 4.6 times in the numerical simulations. The decrease in the penetration depth in the GF-AuNP is made at the expense of bulk sensitivity. The biosensing sensitivity of the GF-AuNP shows up to 7-fold improvement in the carcinoembryonic antigen immunoassay and the GF-AuNP is proven to be a better biosensor. The experimental measurements are in excellent agreement with the theoretical model. This study can be also considered as a guide for the design of plasmonic sensors for detecting multiple substances at different scales, such as cells and proteins.
研究领域:
光学
·
纳米技术
·
生物传感器
·
等离子体学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）