A heterogeneous integration of organic photovoltaics (OPV) with a transparent touch sensor array is demonstrated, as a self-powered electronic skin (e-Skin). OPVs can generate energy and perform shadow sensing for proximity and gesture recognition, while touch sensors can detect pressure and provide spatial information. With better resource management and space utilization, the presented stacked integration of transparent touch-sensing layer and OPVs can evolve into a futuristic energy-autonomous e-Skin that can “see” and “feel.”
Flexible, lightweight, low-power, and low-cost displays are an active area of interest in the electronics community. A printable composite electrothermochromic material was developed consisting of silver nanowires (Ag NWs) and thermochromic powders that exhibit reversible color (phase) change during biasing due to Joule heating. The same layer can function as a display and touch sensor because of its conducting and chromatic properties without additional active layers. The material is suitable for fabricating low-cost, flexible touch color displays for interactive electronic readers, digital posters, and flexible digital signboards.
Featured in IITM Tech Talk: Link
Patterned deposition of highly flexible transparent conducting materials is essential to realise stretchable optoelectronic devices. In this work, we have formulated a nanocomposite ink consisting of Ag NWs and PEDOT:PSS. The printed film shows 86% transparency and 23 Ω/sq sheet resistance, which is suitable for flexible transparent electrode applications. We demonstrate the suitability of this nanocomposite using two applications −a printed transparent flexible antenna radiating at Wi-Fi frequencies and a printed transparent flexible heater suitable for antifogging applications.
Here, we demonstrate a printed transparent PD with an absorber layer based on a nanocomposite of ZnO with silver nanowires (Ag NWs). The nanocomposite shows good optoelectronic properties; Unlike conventional PDs, the photoconductivity decreases under illumination. The Schottky barrier between ZnO and Ag prevents photo-generated electrons in ZnO from moving to the NWs, while the photo-generated holes recombine with the electrons flowing in the NWs leading to a resistance increase. The properties of the nanocomposite make it suitable for single layer, low cost, and large area transparent PDs.
This work is about the formulation of silver nanowire-based ink for printed transparent electrodes and touchpads. The nanowire dimensions and rheology of the ink are adjusted for printing, with a single-layer printed film having a sheet resistance of 30 Ω/□ and a transmittance of 94% at 550 nm. A transparent capacitive touchpad, in the form of a 2 × 2 matrix, is implemented using this ink. The touchpad has a high degree of flexibility, with a resistance variation of less than 2% after 10,000 bending cycles. The formulated nanowire ink can be extended for other flexible and stretchable transparent sensing applications.