Paper as Active Layer in Inkjet-Printed Capacitive Humidity Sensors.
Ontology highlight
ABSTRACT:
SUBMITTER: Gaspar C
PROVIDER: S-EPMC5539845 | biostudies-other | 2017 Jun
REPOSITORIES: biostudies-other
Similar Datasets
Project description:Inkjet printing is an advanced printing technology that has been used to develop conducting layers, interconnects and other features on a variety of substrates. It is an additive manufacturing process that offers cost-effective, lightweight designs and simplifies the fabrication process with little effort. There is hardly sufficient research on tactile sensors and inkjet printing. Advancements in materials science and inkjet printing greatly facilitate the realization of sophisticated tactile sensors. Starting from the concept of capacitive sensing, a brief comparison of printing techniques, the essential requirements of inkjet-printing and the attractive features of state-of-the art inkjet-printed tactile sensors developed on diverse substrates (paper, polymer, glass and textile) are presented in this comprehensive review. Recent trends in inkjet-printed wearable/flexible and foldable tactile sensors are evaluated, paving the way for future research.
| S-EPMC5713153 | biostudies-literature
Project description:Flexible and biodegradable sensors are advantageous for their versatility in a range of areas from smart packaging to agriculture. In this work, we characterize and compare the performance of interdigitated electrode (IDE) humidity sensors printed on different biodegradable substrates. In these IDE capacitive devices, the substrate acts as the sensing layer. The dielectric constant of the substrate increases as the material absorbs water from the atmosphere. Consequently, the capacitance across the electrodes is a function of environmental relative humidity. Here, the performance of polylactide (PLA), glossy paper, and potato starch as a sensing layer is compared to that of nonbiodegradable polyethylene terephthalate (PET). The capacitance across inkjet-printed silver electrodes is measured in environmental conditions ranging from 15 to 90% relative humidity. The sensitivity, response time, hysteresis, and temperature dependency are compared for the sensors. The relationship between humidity and capacitance across the sensors can be modeled by exponential growth with an R2 value of 0.99, with paper and starch sensors having the highest overall sensitivity. The PET and PLA sensors have response and recovery times under 5 min and limited hysteresis. However, the paper and starch sensors have response and recovery times closer to 20 min, with significant hysteresis around 100%. The PET and starch sensors are temperature independent, while the PLA and paper sensors display thermal drift that increases with temperature.
| S-EPMC8512811 | biostudies-literature
Project description:Development of paper-based sensors that do not suffer with humidity interference is desirable for practical environmental applications. In this work, a laser processing method was reported to effectively modulate the cross-sensitivity to humidity of ZnO-based UV (Ultraviolet) sensors printed on paper substrate. The results reveal that the laser induced zinc oxide (ZnO) surface morphology contributes to the super-hydrophobicity of the printed ZnO nanoparticles, reducing humidity interference while enhancing UV sensitivity. Herein, this conducted research highlights for the first time that laser processing is an attractive choice that reduces the cross-sensitivity to water vapor in the UV sensing response of ZnO-based devices printed on paper, paving the way to low-cost and sophisticated paper-based sensors.
| S-EPMC7824355 | biostudies-literature
Project description:We report on the integration of inkjet-printed graphene with a CMOS micro-electro-mechanical-system (MEMS) microhotplate for humidity sensing. The graphene ink is produced via ultrasonic assisted liquid phase exfoliation in isopropyl alcohol (IPA) using polyvinyl pyrrolidone (PVP) polymer as the stabilizer. We formulate inks with different graphene concentrations, which are then deposited through inkjet printing over predefined interdigitated gold electrodes on a CMOS microhotplate. The graphene flakes form a percolating network to render the resultant graphene-PVP thin film conductive, which varies in presence of humidity due to swelling of the hygroscopic PVP host. When the sensors are exposed to relative humidity ranging from 10-80%, we observe significant changes in resistance with increasing sensitivity from the amount of graphene in the inks. Our sensors show excellent repeatability and stability, over a period of several weeks. The location specific deposition of functional graphene ink onto a low cost CMOS platform has the potential for high volume, economic manufacturing and application as a new generation of miniature, low power humidity sensors for the internet of things.
| S-EPMC4663628 | biostudies-other
Project description:Fully inkjet-printed device fabrication is a crucial goal to enable large-area printed electronics. The limited number of two-dimensional (2D) material inks, the bottom-gated structures, and the low current on/off ratio of thin-film transistors (TFTs) has impeded the practical applications of the printed 2D material TFTs. In the search for TFTs with high current ratios, we introduce a stable and efficient method of nitrogen-doped graphene (NDG) ink preparation for inkjet printing by liquid-phase exfoliation. The NDG thin film is print-stacked with molybdenum disulfide (MoS2) by multiple printing passes to construct a MoS2-NDG stack. We demonstrate top-gated fully inkjet-printed MoS2-NDG transistors with silver drain, source, and gate electrodes, and a barium titanate (BaTiO3) dielectric. A 100% inkjet-printed MoS2-NDG vertical 2D active heterostructure layer transistor with a current on/off ratio of 1200 is exhibited. The results may lead towards the development of all-printed 2D material-based transistor switches.
| S-EPMC7179098 | biostudies-literature
Project description:A spoof fingerprint was fabricated on paper and applied for a spoofing attack to unlock a smartphone on which a capacitive array of sensors had been embedded with a fingerprint recognition algorithm. Using an inkjet printer with an ink made of carbon nanotubes (CNTs), we printed a spoof fingerprint having an electrical and geometric pattern of ridges and furrows comparable to that of the real fingerprint. With this printed spoof fingerprint, we were able to unlock a smartphone successfully; this was due to the good quality of the printed CNT material, which provided electrical conductivities and structural patterns similar to those of the real fingerprint. This result confirms that inkjet-printing CNTs to fabricate a spoof fingerprint on paper is an easy, simple spoofing route from the real fingerprint and suggests a new method for outputting the physical ridges and furrows on a two-dimensional plane.
| S-EPMC6648154 | biostudies-literature
Project description:Here, we report an inkjet-printed graphene paper electrode (IP-GPE) for the electrochemical analysis of mercuric ions (Hg(ii)) in industrial wastewater samples. Graphene (Gr) fabricated on a paper substrate was prepared by a facile solution-phase exfoliation method in which ethyl cellulose (EC) behaves as a stabilizing agent. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to determine the shape and multiple layers of Gr. The crystalline structure and ordered lattice carbon of Gr were confirmed by X-ray diffraction (XRD) and Raman spectroscopy. The nano-ink of Gr-EC was fabricated on the paper substance via an inkjet printer (HP-1112) and IP-GPE was exploited as a working electrode in linear sweep voltammetry (LSV) and cyclic voltammetry (CV) for the electrochemical detection of Hg(ii). The electrochemical detection is found to be diffusion-controlled illustrated by obtaining a correlation coefficient of 0.95 in CV. The present method exhibits a better linear range of 2-100 μM with a limit of detection (LOD) of 0.862 μM for the determination of Hg(ii). The application of IP-GPE in electrochemical analysis shows a user-friendly, facile, and economical method for the quantitative determination of Hg(ii) in municipal wastewater samples.
| S-EPMC10251220 | biostudies-literature
Project description:Energy storage devices (ESD) which are intended to power electronic devices, used in close contact of human skin, are desirable to be safe and non-toxic. In light of this requirement, Zn based energy storage devices seem to provide a viable pathway as they mostly employ aqueous based electrolytes which are safe and non-toxic in their functioning. Additionally, having a flexible ESD will play a crucial role as it will enable the ESD to conform to the varying shapes and sizes of wearable electronics which they energize. In this work, we have developed an inkjet-printed Zinc ion battery (IPZIB) with planar electrode configuration over bond paper substrate. Zn has been used as the negative electrode, MnO2 is used as the positive electrode with Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) as the active binder. Conducting tracks of reduced graphene oxide (rGO) are used to construct the current collector on the paper substrate. The fabricated IPZIB delivered a high discharge capacity of 300.14 mAh g-1 at a current density of 200 mA g-1. The energy density of the IPZIB is observed as 330.15 Wh kg-1 at a power density of 220 W kg-1 and retains an energy density of 94.36 Wh kg-1 at a high power density of 1650 W kg-1. Finally, we have demonstrated the capability of the IPZIB to power a LED at various bending and folding conditions which indicates its potential to be used in the next generation flexible and wearable electronic devices.
| S-EPMC10796916 | biostudies-literature
Project description:Nowadays, due to environmental pollution and natural energy consumption caused by waste paper, many researches are being conducted on the reuse of printed-paper. To recycle the paper, de-inking has to be performed. In this article, in order to reduce the use of the commonly used de-inking chemicals, the effect of an atmospheric pressure helium plasma treatment on the de-inking enhancement of printed-paper is studied. Through colorimeter and UV-visible spectrometer measurements the plasma treatment is shown to speed up the de-inking. While SEM observations and FTIR measurements suggest that the paper quality is retained upon plasma treatment, the increase of surface hydrophilicity measured by water contact angle measurements, compared to non-treated paper, is believed to enhance the fiber swelling of the paper and lead to a faster ink removal.
| S-EPMC6773741 | biostudies-literature
Project description:Epidermal electronic systems (EESs) are skin-like electronic systems, which can be used to measure several physiological parameters from the skin. This paper presents materials and a simple, straightforward fabrication process for skin-conformable inkjet-printed temperature sensors. Epidermal temperature sensors are already presented in some studies, but they are mainly fabricated using traditional photolithography processes. These traditional fabrication routes have several processing steps and they create a substantial amount of material waste. Hence utilizing printing processes, the EES may become attractive for disposable systems by decreasing the manufacturing costs and reducing the wasted materials. In this study, the sensors are fabricated with inkjet-printed graphene/PEDOT:PSS ink and the printing is done on top of a skin-conformable polyurethane plaster (adhesive bandage). Sensor characterization was conducted both in inert and ambient atmosphere and the graphene/PEDOT:PSS temperature sensors (thermistors) were able reach higher than 0.06% per degree Celsius sensitivity in an optimal environment exhibiting negative temperature dependence.
| S-EPMC5082757 | biostudies-literature