Highly conductive and bendable gold networks attached on intertwined cellulose fibers for output controllable power paper

Abstract

On-chip energy units are urgently required for the rapid development of the Internet of Things and flexible electronics. Herein, a flexible integrated platform by incorporating paper microfluidic technology with a pencil-drawing approach is presented for self-charging/recharging, self-powered electropolymerization and sensing. By adopting a double bottom-up growth strategy based on paper microfluidics and a wax printing process, gold networks attached on intertwined cellulose fibers with extremely low horizontal sheet resistance (1.6 Ω sq⁻¹) and good vertical conductivity (44.58 S cm⁻¹) were achieved. Then, a low-cost pencil-drawing method based on the porosity of the paper substrate was introduced to overcome the key technical issue of reversible control for fluid and current. Utilizing the unique platform produced, a flexible power paper with a magnesium anode and a Prussian blue cathode was explored. The obtained output controllable power device was applied to drive the electropolymerization of polypyrrole film and a polyaniline network, and electrochemiluminescence images with competitive performance. It is believed that this work offers new insights into the formation of flexible green power and may be instructive for the future design of integrated platforms.