Production and characterization of polyaniline/Co3O4 nanocomposite as a cathode of Zn–polyaniline battery

Abstract

Abstract Co 3 O 4 nanoparticles were prepared by using ethylene glycol as solvent, urea as precipitant and cobalt acetate as precursor. The prepared Co 3 O 4 nanoparticles were incorporated into polyaniline matrix during in situ chemical oxidative polymerization of aniline with different molar ratios of aniline: Co 3 O 4 (40:1, 20:1, 13:1) using (NH 4 ) 2 S 2 O 8 as oxidant in aqueous solution of sodium dodecylbenzene sulfonic acid under N 2 atmosphere. Room temperature conductivities of PANI, PANI/Co 3 O 4 (40:1), PANI/Co 3 O 4 (20:1) and PANI/Co 3 O 4 (13:1) are 3.2 × 10 −4 , 5.1 × 10 −5 , 4.1 × 10 −5 and 1.4 × 10 −5 S/cm respectively, indicating decrease of conductivity with increase of Co 3 O 4 in PANI due to the blocking of charge carriers. These charge carriers do not have sufficient energy to hop between favorable sites. PANI/Co 3 O 4 NCs show paramagnetic behavior at 5 K. Electrochemical studies showed that Zn–PANI/Co 3 O 4 (13:1) battery had delivered maximum discharge capacity (87.1 mAh g −1 ) as compared to Zn–PANI battery (50.1 mAh g −1 ) at constant current of 0.5 mA cm −2 . At constant resistance of 1000 Ω, discharge capacities of Zn–PANI/Co 3 O 4 (13:1) and Zn–PANI battery are 84.6 and 50.8 mAh g −1 , respectively.