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We have interfaced an array of polymer light emitting diodes (OLEDs) fabricated onto a glass substrate to a sheet of paper via a pressure sensitive conducting adhesive. By screen printing a series of capacitive touch pads and connecting tracks onto paper using a low-cost conductive graphite ink, we are able to drive individual pixels in the OLED array via CMOS-based electronics that are also attached to the paper. Three AA batteries are used to power the CMOS electronics, touch pads and the OLED array, with pixels in the array operating at a brightness of up to 210 cd/m2. The work highlights a practical interface between plastic- and paper-based electronics. [ABSTRACT FROM PUBLISHER]

Conducting polymers have been considered for use as cathode materials in rechargeable lithium-ion batteries (LIBs) since 1981 but problems with poor cycling stability, rapid self-discharge, and low energy and power densities have so far limited their applicability. Herein it is shown that nanostructured freestanding conducting polymer composites [e.g., polypyrrole (PPy) and polyaniline (PANI)] can be used to circumvent these shortcomings. Freestanding and binder-free PPy and cellulose-based composites can straightforwardly be used as versatile organic cathode materials for LIBs. The composite, reinforced with chopped carbon filaments (CCFs), exhibited a large active mass loading of approximately 10 mg cm−2, an areal capacity of 1.0 mAh cm−2 (corresponding to 102 mAh g−1), and stable cycling. With an active mass loading of 4.4 mg cm−2, a capacity of 0.22 mAh cm−2 (corresponding to 58 mAh g−1) was found for current densities of 5 A g−1 yielding discharge times of approximately 40 seconds, and a capacity retention of 91 % over 100 cycles was obtained at 0.2 A g−1. The present method constitutes a straightforward approach for the manufacturing of high-performance freestanding electroactive conducting-polymer-based paper-like electrodes for use in inexpensive and sustainable, high-performance organic LIBs. [ABSTRACT FROM AUTHOR]

In this paper, we report a multianode paper-based microbial fuel cell (MFC) capable of generating a power density of 28.4 μW/cm2. This MFC features: 1) flexible multilayered carbon cloth anodes for bacterial attachment and 2) paper reservoirs for holding the anolyte and catholyte for an extended period of time. The hydrophobic barriers in the anodes and paper-based reservoirs were patterned by impregnating and selectively polymerizing photoresist through UV lithography. Upon inoculum/catholyte introduction, a current of 211 μA/cm2 was immediately generated. By using the multianode MFC, the power and current densities increased by 5× and 3×, respectively, compared with a single anode one. The paper-based MFC is expected to be a simple and easy-to-use power source for single-use diagnostic biosensors because even sewage or soiled water in a puddle can become an excellent source for operating MFCs and harvesting electricity through bacterial metabolism. [ABSTRACT FROM PUBLISHER]

Abstract: We have developed flexible top emission organic light-emitting devices by using sputtered Ni films on the parylene coated copy paper substrates. The Ni film grew through the coalescence of the Ni islands nucleated on the cellulose fiber patterns. The parylene, acting as a buffer layer for preventing water absorption, affected the morphological and electrical characteristics of the deposited Ni films. The flexible top emission diode device composed of Ni anode and Ca/Ag semitransparent cathode exhibited a luminance of ∼1 cd/m2 at a driving voltage of 14.5 V. [ABSTRACT FROM AUTHOR]