Electrochemical deposition of leaf stalk-shaped polyaniline doped with sodium dodecyl sulfate on aluminum and its use as a novel type of current collector in lithium ion batteries

Abstract

A cyclic voltammetry (CV) method employing a solution containing H2SO4, aniline and sodium dodecyl sulfate (SDS) as the electrolyte solution was utilized to prepare a SDS-doped polyaniline (PANI) film onto the surface of the commercial aluminum (Al) foil at room temperature generating a novel current collector of SDS-PANI coated Al (denoted as SP/Al). The SDS-doped PANI films prepared in the presence of 2 mM, 5 mM and 10 mM SDS were, respectively, nominated as film SP-2, SP-5 and SP-10. As shown by the SEM images, many irregular particles covered with numerous protuberances were prepared in the absence of SDS, and very interestingly, in the presence of SDS, leaf stalk-shaped particles were fabricated on the surface of the commercial Al foil. As indicated by XRD and FTIR results, the main component of the leaf stalk-shaped particles was PANI. Most important of all, the initial discharge capacities of the commercial LiFePO4 (abbreviated as LFP) on the novel current collectors of SP/Al at 0.2 C were all remarkably higher than that of LFP on the commercial Al foil. Particularly, even at 5 C after 10 cycles, the average discharge capacity of LFP on SP-5/Al (65 mA h g−1) was still about 30% larger than that on the traditional Al foil (50 mA h g−1). Presenting the fact, that using the SDS-doped PANI film coated Al foil to replace the conventional Al foil was a feasible way to promote the electrochemical performance of LFP, is the main dedication of this preliminary work.