Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userHighly reproducible, large scale inkjet-printed Ag nanoparticles-ink SERS substrate
147
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We report the fabrication of a low cost, and highly reproducible large scale surface-enhanced Raman spectroscopy substrate using an inkjet-printed Ag nanoparticle ink (AgNI). The AgNI SERS substrates were evaluated for SERS using BPY as a molecular probe. The printed AgNI dot arrays exhibit an excellent SERS performance and reproducibility. The batch to batch and spot to spot standard deviation value of less than 10 percent was obtained. The results reveal the reproducibility of the AgNI SERS dot arrays and its potential application for SERS substrates.
rate research
Read More
A well-defined insulating layer is of primary importance in the fabrication of passive (e.g. capacitors) and active (e.g. transistors) components in integrated circuits. One of the most widely known 2-Dimensional (2D) dielectric materials is hexagonal boron nitride (hBN). Solution-based techniques are cost-effective and allow simple methods to be used for device fabrication. In particular, inkjet printing is a low-cost, non-contact approach, which also allows for device design flexibility, produces no material wastage and offers compatibility with almost any surface of interest, including flexible substrates. In this work we use water-based and biocompatible graphene and hBN inks to fabricate all-2D material and inkjet-printed capacitors. We demonstrate an areal capacitance of 2.0 pm 0.3 nF cm^(-2) for a dielectric thickness of sim 3 mu m and negligible leakage currents, averaged across more than 100 devices. This gives rise to a derived dielectric constant of 6.1 pm 1.7. The inkjet printed hBN dielectric has a breakdown field of 1.9 pm 0.3 MV cm^(-1). Fully printed capacitors with sub-/mu m hBN layer thicknesses have also been demonstrated. The capacitors are then exploited in two fully printed demonstrators: a resistor-capacitor (RC) low-pass filter and a graphene-based field effect transistor.
We present an investigation of inkjet printed strain gauges based on two-dimensional (2D) materials. The technology leverages water-based and biocompatible inks to fabricate strain measurement devices on flexible substrates such as paper. We demonstrate that the device performance and sensitivity are strongly dependent on the printing parameter (i.e., drop- spacing, number of printing passes, etc.). We show that values of the Gauge Factor up to 125 can be obtained, with large sensitivity (>20%) even when small strains (0.3%) are applied. Furthermore, we provide preliminary examples of heterostructure-based strain sensors, enabled by the inkjet printing technology.
Fully exploiting the properties of 2D crystals requires a mass production method able to produce heterostructures of arbitrary complexity on any substrate, including plastic. Solution processing of graphene allows simple and low-cost techniques such as inkjet printing to be used for device fabrication. However, available inkjet printable formulations are still far from ideal as they are either based on toxic solvents, have low concentration, or require time-consuming and expensive formulation processing. In addition, none of those formulations are suitable for thin-film heterostructure fabrication due to the re-mixing of different 2D crystals, giving rise to uncontrolled interfaces, which results in poor device performance and lack of reproducibility. In this work we show a general formulation engineering approach to achieve highly concentrated, and inkjet printable water-based 2D crystal formulations, which also provides optimal film formation for multi-stack fabrication. We show examples of all-inkjet printed heterostructures, such as large area arrays of photosensors on plastic and paper and programmable logic memory devices, fully exploiting the design flexibility of inkjet printing. Finally, dose-escalation cytotoxicity assays in vitro also confirm the inks biocompatible character, revealing the possibility of extending use of such 2D crystal formulations to drug delivery and biomedical applications.
The surface properties of a substrate are among the most important parameters in the printing technology of functional materials, determining not only the printing resolution but also the stability of the printed features. This paper addresses the wetting difficulties encountered during inkjet printing on homogeneous substrates as a result of improper surface properties. We show that the wetting of a substrate and, consequently, the quality of the printed pattern, can be mediated through the deposition of polymeric layers that are a few nanometers thick. The chemical nature of the polymers determines the surface energy and polarity of the thin layer. Some applications, however, require a rigorous adjustment of the surface properties. We propose a simple and precise method of surface-energy tailoring based on the thermal decomposition of poly(methyl methacrylate) (PMMA) layers. A smooth transition in the wetting occurs when the thickness of the PMMA layer approaches zero, probably due to percolating the underlying surface of the substrate, which enables the inkjet printing of complex structures with a high resolution. In particular, the wetting of three substrate-ink systems was successfully adjusted using the thin polymeric layer: (i) a tantalum-oxide-based ink on indium-tin-oxide-coated glass, (ii) a ferroelectric lead zirconate titanate ink on a platinized silicon substrate, and (iii) a silver nanoparticle ink on an alumina substrate.
Surface-enhanced Raman spectroscopy (SERS) is a sensitive vibrational spectroscopy technique that can enable fast and non-destructive detection of trace molecules. SERS substrates are critical for the advancement of the SERS application. By incorporating SERS substrates into microfluidic devices, the function of microfluidic devices can be extended, and an efficient on-site trace analysis platform with powerful sensing capabilities can be realized. In this paper, we report the fabrication of a rapid and sensitive optofluidic SERS device using a unique Au nanorod array (AuNRA) with a plasmon resonance frequency in the near IR region. The highly stable and reproducible AuNRA were fabricated by a facile dynamic oblique angle deposition technique. A typical spectrum of 4,4-bipyridine (BPY) with enhanced peaks was observed within a few seconds after the injection of an aqueous solution BPY. Time-course measurements revealed an outstandingly quick response of SERS in this system. Using the AuNR microfluidic device, approximately 2x10-12 mole molecules were enough to produce detectable SERS signals. This work demonstrates rapid and sensitive chemical sensing using an optofluidic device equipped with a unique noble metal nanorod array.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
