A graphene-printed paper electrode for determination of H2O2 in municipal wastewater during the COVID-19 pandemic

Graphene prepared through exfoliation process was printed on paper substrate using inkjet-printer and then printed paper electrode was used as an electrochemical sensor for analysis of H2O2 in cyclic voltammetry.

Direct Writing on Paper Substrate to Prepare Silver Electrode Structures for Flexible Sensors

With the rapid development of the electronics industry, electronic products based on silicon and glass substrates electronic products will gradually be unable to meet the rising demand. Flexibility, environmental protection, and low costs are important for the development of electronic products. In this study, an efficient and low-cost method for preparing silver electrode structures by direct writing on paper has been demonstrated. Based on this method, a flexible paper-based sensor was prepared. The liquid printing ink used mainly comprises a precursor liquid without pre-prepared nanomaterials. The precursor liquid is transparent with good fluidity. Simple direct writing technology was used to write on the paper substrate using the precursor ink. When the direct-writing paper substrate was subsequently heated, silver nanostructures precipitated from the precursor liquid ink onto the paper substrate. The effect of different temperatures on the formation of the silver nanostructures and the influence of different direct writing processes on the structures were studied. Finally, a paper-based flexible sensor was prepared for finger-bending signal detection. The method is simple to operate and low in cost and can be used for the preparation of environment-friendly paper-based devices.

Advantages of graphene technologies in the design of antenna systems for the Internet of Things in the decimeter range of cellular operators (LTE, GSM, 5G)

The characteristics and resistance to external influences of flexible graphene antennas are considered. In particular, the analysis of the influence of single and cyclic bends at different cycle times is carried out. Resistance to water of such antennas is analysed. The results of characteristics comparison of the literature data with the results obtained by the authors are presented. The design of a flexible graphene eco-friendly two-layer antenna on a paper substrate operating in the LTE frequency range has been proposed. The technology discussed in this report will help fill the gap in the literature in eco-friendly double-sided graphene printing technologies. The literature review shows that the development of graphene inks for printing on flexible substrates has made a breakthrough in the development of flexible electronics due to their unique advantages. The influence of edge effects on the change in the graphene surface resistance at the edges of the manufactured sample is estimated.

Atomic, surface morphology, structural and electrochemical properties of silver nanoparticles-polypyrrole composite film grown on cellulosic paper substrate

In this work, we describe a simple strategy for the preparation of a low-cost electrode material based on polypyrrole (PPy) film grown on an insulating cellulosic paper substrate (Pap) via in-situ oxidative polymerization technique and functionalized by silver nanoparticles (AgNPs) uniformly dispersed on its surface. The properties of the obtained AgNPs-PPy composites were characterized using FTIR-ATR spectroscopy (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscope (SEM) coupled with energy dispersive X-ray spectrometry (EDX), X-ray diffraction spectroscopy (DRX) and electrochemical impedance spectroscopy (SIE).