ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Pan Gu,Jiping Wang,Peter Müller-Buschbaum,Dongming Qi,Qi Zhong
To overcome the drawbacks of existing infrared detectors, infrared thin film detectors based on microgels and gold nanorods (Au NRs) are investigated. The microgels with a linear shrinkage of the hydrodynamic diameter between 10 and 55 °C are copolymerized by monomers di(ethylene glycol) methyl ether methacrylate, oligo(ethylene glycol) methyl ether methacrylate, and acrylic acid with a molar ratio of 1:1:1. Homogenous thin films are obtained by spin coating from an aqueous solution on silicon substrates. Upon heating in a water vapor atmosphere, the film thickness of the hybrid films linearly decreases. Heat generation from a plasmon resonance enhanced absorption of the infrared radiation by the Au NRs triggers a linear shrinkage in the hybrid microgel-Au NR films as well. A linear correlation between the film thickness and the applied infrared power density is observed. The sensitivity is enhanced by a slight increase in the amount of Au NRs in the films. Infrared detectors are constructed from the hybrid microgel-Au NR films by adding two electrodes via deposition of two silver layers at the film ends. By monitoring the ohmic resistance, the intensity of the incident infrared light can be obtained. The detectors not only possess a good reversibility and fast response rate but also show a high stability after the resistance measurements. Compared with the traditional infrared detectors, the infrared thin film detectors based on microgels are sensitivity adjustable. Thus, they can be promising candidates for replacing expensive inorganic infrared detectors in areas of daily life applications.
研究领域:
材料科学
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纳米技术
·
光学工程
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2020
·
IF 3.557
Qi Zhong,Chen Chen,Lei Mi,Ji-Ping Wang,Jing Yang,Guang-Peng Wu,Zhi-Kang Xu,Robert Cubitt,Peter Müller-Buschbaum
The linear shrinkage behavior in thermoresponsive diblock copolymer films and its potential application in temperature sensors are investigated. The copolymer is composed of two thermoresponsive blocks with different transition temperatures (TTs): di(ethylene glycol) methyl ether methacrylate (MEO2MA; TT1 = 25 °C) and poly(ethylene glycol) methyl ether methacrylate (OEGMA300; TT2 = 60 °C) with a molar ratio of 1:1. Aqueous solutions of PMEO2MA-b-POEGMA300 show a three-stage transition upon heating as seen with optical transmittance and small-angle X-ray scattering: dissolution (T < TT1), self-assembled micelles with core–shell structure (TT1 < T < TT2), and aggregation of collapsed micelles (T > TT2). Due to the restrictions in the polymer chain arrangement introduced by the solid Si substrate, spin-coated PMEO2MA-b-POEGMA300 films exhibit an entirely different internal structure and transition behavior. Neutron reflectivity shows the absence of an ordered structure normal to the Si substrate in as-prepared PMEO2MA-b-POEGMA300 films. After exposure to D2O vapor for 3 h and then increasing the temperature above its TT1 and TT2, the ordered structure is still not observed. Only a D2O enrichment layer is formed close to the hydrophilic Si substrate. Such PMEO2MA-b-POEGMA300 films show a linear shrinkage between TT1 and TT2 in a D2O vapor atmosphere. This special behavior can be attributed to the synergistic effect between the restrained collapse of the PMEO2MA blocks by the still swollen POEGMA300 blocks and the impedance of chain arrangement by the Si substrate. Based on this unique behavior, spin-coated PMEO2MA-b-POEGMA300 films are further prepared into a temperature sensor by implementing Ag electrodes. Its resistance decreases linearly with temperature between TT1 and TT2.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano-Micro Letters
·
2022
·Vol. 14
·期 1
·1-14
·
IF 23.655
Zhou Rui,Wang Yansong,Liu Ziyu,Pang Yongqiang,Chen Jianxin,Kong Jie
Abstract Combining 3D printing with precursor-derived ceramic for fabricating electromagnetic (EM) wave-absorbing metamaterials has attracted great attention. This study presents a novel ultraviolet-curable polysiloxane precursor for digital light processing (DLP) 3D printing to fabricate ceramic parts with complex geometry, no cracks and linear shrinkage. Guiding with the principles of impedance matching, attenuation, and effective-medium theory, we design a cross-helix-array metamaterial model based on the complex permittivity constant of precursor-derived ceramics. The corresponding ceramic metamaterials can be successfully prepared by DLP printing and subsequent pyrolysis process, achieving a low reflection coefficient and a wide effective absorption bandwidth in the X-band even under high temperature. This is a general method that can be extended to other bands, which can be realized by merely adjusting the unit structure of metamaterials. This strategy provides a novel and effective avenue to achieve “target-design-fabricating” ceramic metamaterials, and it exposes the downstream applications of highly efficient and broad EM wave-absorbing materials and structures with great potential applications.
研究领域:
材料科学
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电磁学
·
先进制造
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Chem
·
2018
·
IF 14.104
Qi Zhang,Si-Jia Rao,Tao Xie,Xin Li,Tian-Yi Xu,Da-Wei Li,Da-Hui Qu,Yi-Tao Long,He Tian
Muscle tissue performs crucial contraction/extension motions that generate mechanical force and work by consuming chemical energy. Inspired by this naturally created biomolecular machine, artificial molecular muscles are designed and synthesized to undertake linear actuation functions. However, most of these muscle-like actuators are performed at large ensembles, while to realize the nanoscale actuation at the single- to few-molecule level remains challenging. Herein, we developed an artificial muscle-like molecular actuator that can reversibly control the proximity of the attached nano-objects, gold nanoparticles, within the single-molecule length level by its stimuli-responsive muscle-like linear contraction/extension motion. The molecular actuation motion is accompanied by an optical signal output resulting from the plasmonic resonance properties of gold nanoparticles. Meanwhile, the thermal noise of the muscle-like molecular actuator can be overcome by integrating the optical signal over a sufficiently long period.
研究领域:
纳米技术
·
分子工程
·
材料科学
·
光学
✓ 已验证
DOI
高影响因子
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