Thieno3,2-bthiophene-Bridged Polypyrrole Film-Based Micro-Supercapacitors

Polypyrrole, one of the famous conventional conductive polymers, has been well studied in the past decades. Due to the rational controlling methods of morphology and structure, polypyrrole-based materials have shown great potential in the field of energy conversion and storage. For example, polypyrrole could contribute excellent pseudocapacitance as electrode material for supercapacitors. However, synthesis of two-dimensional polypyrrole or ultra-thin films remains a challenge because of the easy aggregation and poor solubility features. In this work, the electron-rich thieno3,2-bthiophene unit is used to bridge pyrrole monomers to produce four-armed bipyrrole monomer. At liquid-liquid interface, conventional oxidative polymerization reaction can take place and uniform polypyrrole film with large area can be easily produced. Through directly laser scribing, interdigitated micro-supercapacitors based on Au layer supported polypyrrole film can be produced. After evaluation through cyclic voltammetry curves, impedance curves, etc., the micro-supercapacitors show areal specific capacitance of 1.10 mF/cm², volumetric specific capacitance of 68.4 F/cm³, equivalent series resistance（ESR） of 4.2 Ω. The maximum energy density and power density of as-prepared micro-supercapacitors reach 9.50 mW·h/cm³ and 1 433 W/cm³, respectively.