Vertical organic electrochemical transistors (OECTs) have been manufactured solely using screen printing. The OECTs are based on PEDOT:PSS (poly(3,4-ethylenedioxythiophene) doped with poly (styrene sulfonic acid)), which defines the active material for both the transistor channel and the gate electrode. The resulting vertical OECT devices and circuits exhibit low-voltage operation, relatively fast switching, small footprint and high manufacturing yield; the last three parameters are explained by the reliance of the transistor configuration on a robust structure in which the electrolyte vertically bridges the bottom channel and the top gate electrode. Two different architectures of the vertical OECT have been manufactured, characterized and evaluated in parallel throughout this report. In addition to the experimental work, SPICE models enabling simulations of standalone OECTs and OECT-based circuits have been developed. Our findings may pave the way for fully integrated, lowvoltage operating and printed signal processing systems integrated with e.g. printed batteries, solar cells, sensors and communication interfaces. Such technology can then serve a low-cost base technology for the internet of things, smart packaging and home diagnostics applications.

Demands in the storage of energy have increased for many reasons, in part driven by household photovoltaics, electric grid balancing, along with portable and wearable electronics. These are fast-growing and differentiated applications that urge for large volume and/or highly distributed electrical energy storage, which then requires environmentally friendly, scalable and flexible materials and manufacturing techniques. However, the limitations on current inorganic technologies have driven research efforts to explore organic and carbon-based alternatives. Here, we report a conducting polymer:cellulose composite that serves as the active material in supercapacitors which has been incorporated into all printed energy storage devices. These devices exhibit a specific capacitance of ≈ 90 F/g and an excellent cyclability (>10,000 cycles). Further, a design concept coined 'supercapacitors on demand' is presented, which is based on a printing-cutting-folding procedure, that provide us with a flexible production protocol to manufacture supercapacitors with adaptable configuration and electrical characteristics.

Here, we report all-screen printed display driver circuits, based on organic electrochemical transistors (OECTs), and their monolithic integration with organic electrochromic displays (OECDs). Both OECTs and OECDs operate at low voltages and have similar device architectures, and, notably, they rely on the very same electroactive material as well as on the same electrochemical switching mechanism. This then allows us to manufacture OECT-OECD circuits in a concurrent manufacturing process entirely based on screen printing methods. By taking advantage of the high current throughput capability of OECTs, we further demonstrate their ability to control the light emission in traditional light-emitting diodes (LEDs), where the actual LED addressing is achieved by an OECT-based decoder circuit. The possibility to monolithically integrate all-screen printed OECTs and OECDs on flexible plastic foils paves the way for distributed smart sensor labels and similar Internet of Things applications.

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Electronic matrix addressed displays capable of presenting arbitrary grayscale images typically require complex device architectures including switching components to provide unique pixel addressability. Here, we demonstrate high-yield manufacturing of passive matrix addressed electrochromic displays on flexible substrates by solely using screen printing. The simple pixel architecture, obtained by printing only three active layers on top of each other, concurrently provides both the electrochromic functionality and the critical non-linear pixel switching response that enables presentation of arbitrary grayscale images in the resulting passive matrix addressed displays. The all-printed display technology exhibits unprecedented performance and is further verified by dynamic QR codes, to exemplify utilization within authentication, packaging, or other emerging Internet of Things applications requiring a low-cost display for data visualization.