Advanced Optical Materials
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2018
·Vol. 6
·期 17
·1800436
·
IF 7.43
Nannan Li,Hang Yin,Xiaolu Zhuo,Baocheng Yang,Xiao-Ming Zhu,Jianfang Wang
Surface-enhanced infrared absorption (SEIRA) spectroscopy, the enhancement of molecular vibrational signals using resonant metal nanostructures, has recently attracted much attention owing to its potential use in molecular detection in chemistry, biology, and medicine. This study reports on the growth of high-aspect-ratio metal nanocrystals and their application for SEIRA. Highly uniform Ag nanorods are synthesized through Au nanobipyramid-directed Ag overgrowth, and Au nanotubes are further prepared through the galvanic replacement reaction from the Ag nanorods. Both Ag nanorods and Au nanotubes possess narrow distributions in diameter and length and exhibit highly tunable plasmon wavelengths in the near and mid-infrared regions. The Ag nanorods are employed as plasmonic nanoantennas to enhance the molecular vibration signals of cetyltrimethylammonium bromide molecules that are embedded in a mesostructured silica layer coated on the Ag nanorods. The dimension-dependent SEIRA performances are carefully investigated both experimentally and numerically. The experimental and simulated SEIRA enhancement factors are in good agreement and both determined to be of the order ≈10 3 . The results point out a promising route to the utilization of chemically synthesized, colloidal metal nanostructures as SEIRA platforms. The synthesis method also provides high-quality metal nanostructures for exploring various plasmon-based optical and sensing applications in the infrared region.
研究领域:
化学
·
纳米科技
·
光学
·
生物医学工程
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Guohui Li,Wen-Bin Gong,Tianlun Qiu,Shan Cong,Zhigang Zhao,Renzhi Ma,Yuichi Michiue,Takayoshi Sasaki,Fengxia Geng
Surface-enhanced Raman scattering (SERS) employing a non-noble substrate in comparison with conventional noble-metal ones offers advantages of low cost and rich selection of candidates; however, its application has been seriously hindered by its unsatisfactory detection sensitivity, poor uniformity, and undesirable modification of vibrational signals via changing the orientation and/or polarizability of probe molecules. Here, an unusually sensitive but nonselective enhancement was achieved by employing titanium carbide sheets modified with aluminum oxyanions in situ as active supports for Raman measurement. The analyte molecules adopted a conformation similar to what they adopt on a bare substrate, while closely interacting with the aluminum oxyanion surface, which leads to the rare observation of highly sensitive but nonselective enhancement with a detection limit close to the pM level. With the substrate surface roughness in the nanometer region, an outstanding uniformity with a relative standard deviation of less than 4.3% was achieved. In addition, the SERS effect on the modified titanium carbide sheets was shown to be applicable to a wide range of analyte molecules, including both organic dyes and trace harmful compounds. The success of the work demonstrates the feasibility of surface tuning to improve the SERS effect, and it introduces a new window for two-dimensional materials in SERS applications.
研究领域:
材料科学
·
分析化学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shan Lu,Zeyu Ma,Xiaodong Huang,Yuhao Wu,Zheng Wang,Jianbo Liu,Mingwei Ding,Liguo Qin,Guangneng Dong
Recently, owing to their high sensitivity, spider-inspired crack strain sensors have received considerable attention. However, their short linear range leads to severe limitations in their application in sports health monitoring. Herein, we fabricated a cracked hydrogel strain sensor with a wide linear range using κ-carrageenan and polyacrylamide. This crack hydrogel strain sensor has a wide linear range (ε = 250 %) and excellent linearity (R 2 ≈ 0.999) while ensuring high sensitivity (gauge factor GF = 2.2). Moreover, this sensor is sensitive to small vibration signals. We compared it with a traditional hydrogel strain sensor and analyzed how crack appeared. Finally, we presented the application of this sensor in human health monitoring and detection of multiaxial strains.
研究领域:
材料科学
·
生物医学工程
·
传感器与执行器
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Chenkai Zhu,Zhenzong Shao,Baoning Chang,Yong Wang,Ting Yu,Changyong Huang,Yang Yang,Xilun Ding,Fei Liu,Wuxiang Zhang
Flexible strain sensors based on hydrogels have shown promising application prospects in artificial tissue and body deformation monitoring. However, hydrogel-based sensors with ideal structural performance, self-healing ability, strain detection, and tissue adhesion remain challenging. Herein, a dual-network hydrogel (PG-B-T) flexible sensor based on poly(vinyl alcohol) (PVA) and gelatin was developed, which were multidynamically cross-linked via the one-pot approach. The noncovalent bonds of gelatin cross-linked by tannic acid (TA) could form the first network and impart structural stability with antibacterial performance, while the second network constructed with reversible borate ester bonds by PVA and borax showed the capability of self-healing and electric conductivity. As such, the prepared PG-B-T hydrogel demonstrated exceptional ductility (strain >1000%) and high sensitivity (GF = 2.51). In air or an underwater environment, the PG-B-T hydrogel can perform a wide working range, such as self-healing capability, electrical properties, and sensing properties. Meanwhile, the hydrogen bonds of gelatin enabled strong adhesion to some classic substrates, not only allowing the hydrogel to monitor body movements and detect vocal vibration signals but also achieving underwater information transmission of Morse code via finger movement. Consequently, this work provided a significant strategy for developing multifunctional hydrogels as strain-sensitive sensors that could conveniently and effectively detect motion variation.
研究领域:
材料科学
·
生物医学工程
·
传感器与执行器
·
纳米技术
·
软体机器人
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）