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51.
The complementary electrochromic device, where the optical transmittance changes upon the flow of cations back and forth between anodic and cathodic electrodes, operates in a rocking-chair fashion if it can inherently self-discharge. Herein, the first demonstration of a dual-mode electrochromic platform having self-coloring and self-bleaching characteristics is reported, which is realized by sandwiching zinc metal within a newly-designed Prussian blue (PB)-WO3 rocking-chair type electrochromic device. It is demonstrated that the redox potential differences between the zinc metal and the WO3/PB electrodes endow the self-color-switching of these electrodes. By employing a hybrid electrolyte of Zn2+/K+, it is further shown that the colored PB-WO3 rocking-chair device is capable of spontaneously bleaching when the anodic and cathodic electrodes are coupled. This dual-mode light-control strategy enables the electrochromic devices to exhibit four distinct optical states with the highest optical contrast of 72.6% and fast switching times (<5 s for the bleaching/coloration processes). Furthermore, the built-in voltage of the dual-mode electrochromic devices not only promotes energy efficiency, but also augments the bistability of the devices. It is envisioned that the broad implication of the present platform is in the development of self-powered smart windows, colorful displays, optoelectronic switches, and optical sensors. 相似文献
52.
Ping Zhang Xingrui Tong Yi Gao Zhongyuan Qian Ruirui Ren Chenchen Bian Jinhui Wang Guofa Cai 《Advanced functional materials》2023,33(41):2303270
Polymer-dispersed liquid crystal (PDLC) devices are truly promising optical modulators for information display, smart window as well as intelligent photoelectronic applications due to their fast switching, large optical modulation as well as cost-effectiveness. However, realizing highly soft PDLC devices with sensing function remains a grand challenge because of the intrinsic brittleness of traditional transparent conductive electrodes. Here, inspired by spiderweb configuration, a novel type of silver nanowires (AgNWs) micromesh-based stretchable transparent conductive electrodes (STCEs) is developed to support the realization of soft PDLC device. Benefiting from the embedding design of AgNWs micromesh in polydimethylsiloxane (PDMS), the STCEs can maintain excellent electrical conductivity and transparency even in various extreme conditions such as bending, folding, twisting, stretching as well as multiple chemical corrosion. Further, STCEs with the embedded AgNWs micromesh endow the assembled PDLC device with excellent photoelectrical properties including rapid switching speed (<1 s), large optical modulation (69% at 600 nm), as well as robust mechanical stability (bending over 1000 cycles and stretching to 40%). Moreover, the device displays the pressure sensing function with high sensitivity in response to pressure stimulus. It is conceivable that AgNWs micromesh transparent electrodes will shape the next generation of related soft smart electronics. 相似文献
53.
In the area of wireless communication technologies, 6LoWPAN leverages the extensive capabilities of IPv6, even within the constraints imposed by resource-limited devices, particularly within wireless sensor networks (WSNs). The integration of 6LoWPAN into modern solutions for implementing the IPv6-based Internet of Things (IoT) is becoming increasingly important. In this paper, a sensor monitoring and notification system specifically designed for deployment over 6LoWPAN has been proposed. Multipurpose capability, scalability, and ease of deployability are the main features of the proposed system. Its architecture reflects the highest degree of flexibility and allows for a variety of use cases encountered in practical scenarios. In addition, a web interface has been developed as part of the comprehensive system architecture. This interface enables efficient management of the entire system and facilitates connection for new users and seamless integration of additional sensors. By encapsulating complex functions in a user-friendly interface, the system promotes accessibility, convenience, and an enhanced user experience. The proposed system overcomes the limitations of current approaches, thereby creating new opportunities. The flexibility of the proposed system allows it to be applied to various use cases. 相似文献
54.
Yi Wei Wei Wang Zhennan Wang Hang Yang Xinyu You Yunna Zhao Peipei Dang Hongzhou Lian Jianhua Hao Guogang Li Jun Lin 《Advanced functional materials》2023,33(2):2205829
Bismuth (Bi3+)-included lead-free metal halide (LFMH) materials attract much attention in lighting, display, photodetectors, X-ray detectors, and photovoltaic fields, due to the tunable luminescence and optoelectronic performance in response to crystal and electronic structure, morphology, and particle sizes. This review summarizes Bi3+-included LFMH materials about their preparation approach, crystal and electronic structure properties, luminescence performance, and emerging applications. Notably, Bi3+ ions not only can act as framework cation to construct stable LFMH structure, but can also incorporate into LFMH materials as activators or sensitizers to generate remarkable luminescence tuning and band engineering. The Bi3+ effect on the luminescence and optoelectronic properties of LFMH materials, including, promotion of exciton localization, enhancement of light absorption in near-ultraviolet region, action as sensitizer ions to transfer energy to rare earth or transition metal ions and emission of highly-efficient light is systematically summarized. The proposed structure-luminescence relationship offers guidance for the optimization of current Bi3+-included LFMH materials and the exploitation of new LFMH derivatives. 相似文献
55.
Jakub Kołacz Henry G. Gotjen Robel Y. Bekele Jason D. Myers Jesse A. Frantz Michael Ziemkiewicz 《Liquid crystals》2020,47(4):531-539
ABSTRACTIn a planar dielectric waveguide, weak confinement of a propagating mode in a high index core leads to a measurable evanescent interaction with the cladding. In this work, we study the effect of a reorientable anisotropic cladding on the behaviour of Transverse Electric (TE) and Transverse Magnetic (TM) mode polarisations using a liquid crystal (LC)-clad waveguide architecture. The polarised evanescent field of a guided mode interacts with a voltage-tunable birefringent LC cladding to deflect an out-coupled beam. Experimental measurements are coupled with a theoretical framework and show good consistency with simulation results. We isolate the effect of mode confinement by changing the thickness of the high index core. Interactions between the LC index ellipsoid and the mode polarisation are probed by changing the initial alignment of the LC. Finally, we examine the difference in deflection between TE and TM modes, which incorporates both a change in mode confinement and a difference in LC index components. 相似文献
56.
Schalley CA Lützen A Albrecht M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(5):1072-1080
Functional molecules require a high degree of complexity which is difficult to achieve by covalent synthesis. This article discusses supramolecular approaches to the creation of larger architectures through noncovalent bonds, self-assembly, and template strategies. It highlights selected examples for the structural and conformational control of function and attempts to identify difficulties and challenges which may arise in future. 相似文献
57.
58.
A bifunctional amido-thiophene namely hexamethylene (bis-3-thiophene acetamide) (HMTA) was synthesized by the reaction of 3-thiophene acetic acid with hexamethylene diamine. Copolymerization in the presence of thiophene was achieved electrochemically in tetrabutylammonium tetrafluoroborate/acetonitrile (TBAFB/AN). Spectroelectrochemical analysis of the resulting copolymer [P(HMTA-co-Th)] reflected electronic transitions at 505 nm, 740 nm and ∼1000 nm, revealing π to π* transition, polaron and bipolaron band formation respectively. Switching ability was evaluated by a kinetic study via measuring the transmittance (%T) at the maximum contrast. Dual type polymer electrochromic devices (ECDs) based on P(HMTA-co-Th) and poly(ethylene dioxythiophene) (PEDOT) have been constructed. Spectroelectrochemistry, switching ability and stability of the devices were investigated by UV-vis spectroscopy and cyclic voltammetry. These devices exhibit low switching voltages (between 0.0 V and +1.6 V), short switching times with reasonable switching stability under atmospheric conditions. 相似文献
59.
Functional organic molecular materials and conjugated oligomers or polymers now allow the low-cost fabrication of thin films for insertion into new generations of electronic and optoelectronic devices. The performance of these devices relies on the understanding and optimization of several complementary processes. Our goal is to discuss the relationship between the molecular stacking structures and their optoelectronic properties that are of importance in all these areas. The concept of intermolecular interaction should be taken here in the special sense that is inter-dipole coupling. Specifically, we will address the impact of inter-dipole interaction between adjacent molecules in aggregate state on the solid-state emission properties. 相似文献
60.
Margaret Sequeira Dermot Diamond Antoine Daridon Jan Lichtenberg Sabeth Verpoorte N. F. de Rooij 《Trends in analytical chemistry : TRAC》2002,21(12):816-827
Progress in the development of a micro-fluidic system for colorimetric monitoring of ammonia in drinking and wastewater is described. The ultimate goal is to have a miniaturised instrument that can produce accurate, reliable measurements, is easy to operate, has minimal power consumption, and can operate autonomously for a year. In this study, the indophenol reaction is incorporated into a simple, reliable analytical micro-fluidic system. Absorbance measurements for the blue ammonia-indophenol complex formed in the micro-fluidic system are shown. A key issue is the limiting stability of hypochlorite, a reagent used in the assay. The effects of hypochlorite concentration and impurities on the stability of hypochlorite are investigated and discussed. Decomposition is shown to be very dependent on the presence of heavy-metal impurities. With low levels of these catalytic metals and careful storage, hypochlorite has been shown to be stable for over a year. 相似文献