Name of the conference: Materials Research Society (MRS) Conference
Date of publication: 1-6 December 2019
Abstract: Typical fabrication methods, such as photolithography and rolling/stacking, that are commonly used in conventional electronics and energy storage systems respectively, have caused the devices to lack a variety of form factors and flexibility needed for countless new Internet-of-Things applications. In the past decade, the development of digital printing technology in the field of printed electronics, has triggered an explosion of new ideas and alternative fabrication strategies that led to lean and cost-efficient manufacturing processes. In this work, the digital nature of inkjet printer was utilised to fabricate multifunctional energy storage sources in the form of casual letters in text. A new font style of the Latin alphabet was developed so that each character assembles a planar supercapacitor, able to be aesthetically and seamlessly connected, either in series or parallel configuration. A nanoparticle-based silver current collector, a nanoparticle-based nickel (II) oxide (NiO) active electrode material and a transparent ionic liquid/ultraviolet-cured triacrylate polymer-based solid-state electrolyte, were chosen as model materials to explore the feasibility of the proposed concept. The model letter-supercapacitors were able to deliver up to 55 mF·cm-2 and handle scan rates up to 500 mV·s-1 at a voltage window of 2.5 V. This approach underlines the exceptional applicability of the inkjet-printed letter-supercapacitors as a fabrication strategy towards multifunctional power sources with versatile form factors that lie far beyond what conventional fabrication technologies can achieve. The letter-supercapacitors can be used as energy storage units for electronic books, paper electronics and smart textiles with the potential of the proposed concept to be extended beyond interconnects and energy storage to seamless printed sensors and other electronic components.