Resistive Water Level Sensors Based on AgNWs/PEDOT:PSS-g-PEGME Hybrid Film for Agricultural Monitoring Systems
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ABSTRACT:
SUBMITTER: Baek S
PROVIDER: S-EPMC9096971 | biostudies-literature | 2022 Apr
REPOSITORIES: biostudies-literature
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Project description:The thermoelectric properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PedotPSS) and tellurium-PedotPSS (Te-PedotPSS) hybrid composites were enhanced via simple chemical treatment. The performance of thermoelectric materials is determined by their electrical conductivity, thermal conductivity, and Seebeck coefficient. Significant enhancement of the electrical conductivity ofPedotPSS and Te-PedotPSS hybrid composites from 787.99 and 11.01 to 4839.92 and 334.68 S cm(-1), respectively was achieved by simple chemical treatment with H2SO4. The power factor of the developed materials could be effectively tuned over a very wide range depending on the concentration of the H2SO4 solution used in the chemical treatment. The power factors of the developed thermoelectric materials were optimized to 51.85 and 284 μW m(-1) K(-2), respectively, which represent an increase of four orders of magnitude relative to the corresponding parameters of the untreated thermoelectric materials. Using the Te-PedotPSS hybrid composites, a flexible thermoelectric generator that could be embedded in textiles was fabricated by a printing process. This thermoelectric array generates a thermoelectric voltage of 2 mV using human body heat.
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Project description:Conducting polymer scaffolds combine the soft-porous structures of scaffolds with the electrical properties of conducting polymers. In most cases, such functional systems are developed by combining an insulating scaffold matrix with electrically conducting materials in a 3D hybrid network. However, issues arising from the poor electronic properties of such hybrid systems, hinder their application in many areas. This work reports on the design of a 3D electroactive scaffold, which is free of an insulating matrix. These 3D polymer constructs comprise of a water soluble conducting polymer (PEDOT:PSS) and multi-walled carbon nanotubes (MWCNTs). The insertion of the MWCNTs in the 3D polymer matrix directly contributes to the electron transport efficiency, resulting in a 7-fold decrease in resistivity values. The distribution of CNTs, as characterized by SEM and Raman spectroscopy, further define the micro- and nano-structural topography while providing active sites for protein attachment, thereby rendering the system suitable for biological/sensing applications. The resulting scaffolds, combine high porosity, mechanical stability and excellent conducting properties, thus can be suitable for a variety of applications ranging from tissue engineering and biomedical devices to (bio-) energy storage.
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Project description:As a poly (3,4-ethylenedioxythiophene) doped with poly (styrene sulfonate), PEDOT:PSS is well known for its conductive polymer in a field of organic electronics. PEDOT:PSS can be widely operated as electronics under low temperature conditions; however, the layer can be easily damaged by high temperature conditions, while in fabrication or in the operation of electronics. Therefore, enhancing the thermal stability of PEDOT:PSS can be a novel strategy for both fabrication and operating varieties. Herein, PEDOT:PSS is the surface-treated with tannic acid to increase the thermal stability. A large number of phenols in tannic acid not only provide UV absorption ability, but also thermal stability. Therefore, tannic-treated PEDOT:PSS film sustained 150 °C for 96 h because of its initial conductivity. Moreover, surface properties and its bonding nature was further examined to show that the tannic acid does not damage the electrical and film properties. The method can be widely used in the field of organic electronics, especially because of its high stability and the high performance of the devices.
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Project description:In the past decade, the development of medical health and human-computer interfaces has put forward requirements for the non-contact application of flexible electronics. Among them, flexible humidity sensors play an important role in the field of non-contact sensing by virtue of their rapid response to humidity changes. In this paper, a flexible paper-based humidity sensor with high performance was fabricated by embedded Au@AgNWs electrodes on filter paper through spraying and electroplating (EP) methods. Benefitting from the moisture-sensitive properties of the paper and the tight integration of the electrodes into the filter paper, the sensor shows the humidity monitoring range of 33-100% RH, large response value of I/I0 = 1958, excellent linearity of R2 = 0.99662 and hysteresis performance under the low excitation voltage of only DC 1 V. In addition, the good biocompatibility of the paper-based humidity sensor endows it with multifunctional applications for breath detection, non-contact applications and food security monitoring. Easy access to raw materials and convenient preparation methods of this work provide new ideas for the development and commercialization of flexible humidity sensors.
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