Urea-based fuel cells on paper with micro-watt power generation to drive low power circuits

Abstract

This work demonstrates the application of a urea-powered paper-based fuel cell (PFC) with Hydrogen Peroxide (H 2 O 2 ) as the oxidant to drive a exible electronic circuit (ring oscillator (RO)), for the rst time.Herein, the electrochemical performance of membraneless PFCs is studied by employing different nonprecious electrodes, such as, Nickel-mesh, Toray carbon paper(CP) and Nickel Cobalt nanoparticles supported on reduced Graphene Oxide loaded on the CP (NiCo@rGo@CP). A single-PFC with Ni-Co@rGo@CP as electrodes delivers a peak power density (P max ) of 55 µW cm − 2 , maximum current density (J max ) of 371 µA cm − 2 and an open-circuit voltage (OCV) of 0.7 V at 3 M urea. A membranebased PFC assembled onto an anion exchange membrane with Ni-Co@rGo@CP electrodes, delivers a P max of approx 70 µW cm − 2 , J max of ≈ 500 µA cm − 2 and an OCV of 0.7 V at 3 M urea. Subsequently, a stack of two membrane-based PFCs delivers an OCV of ≈ 1.4 V for 400 seconds. Finally, this stack is employed as a power source to drive a RO. The measured frequency and peak-to-peak voltage are 37.52 kHz and 1.04 V, respectively. This demonstration opens a window to implement self-contained exible electronic system using PFC as power source with minimal e-waste.