Fabrication of Freestanding Flexible Electrode Based on PEDOT:PSS Polymer Composite for Li – S Batteries

Abstract

Currently, Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is considered a promising composite in energy conversion and storage devices due to its high electrical conductivity, chemical stability, outstanding flexibility and great electrochemical properties. Owing to its favorable mechanical and electrical properties PEDOT:PSS has wide applications in transparent electrodes, photovoltaics, fuel cells, supercapacitors and lithium-ion batteries [1-2]. Flexible free-standing sulfur @ MWCNT @ PEDOT:PSS composite films might be prepared using various techniques such as vacuum infiltration, facile solution mixing method, rod-coating technique, hydrothermal method, and doctor-blade technique [3]. In our review, we synthesized PEDOT:PSS @ sulfur@ MWCNT composite film by a doctor-blade technique onto the polypropylene (PP) substrate. First, the cathode composite was prepared by mixing multi-walled carbon nanotubes (MWCNT) composite with a sulfur content 1:1, PEDOT:PSS water-based dispersion and DMSO as a solvent to form a homogeneous slurry. The slurry was coated onto PP substrate by doctor-blade method and subsequently dried in a vacuum oven. Furthermore, sulfur @ MWCNT @ PEDOT:PSS film was structurally characterized by scanning electron microscopy (SEM) analysis. SEM images show the flexible film, which exhibits a network structure formed by interpenetration of MWCNTs and PEDOT:PSS. Sulfur nanoparticle clusters are surrounded by CNT networks, forming intimate interfaces with each other. According to EDS results, uniform distribution of each element can be observed. Acknowledgement This work was supported by the research projects АР08052143 “Development of Wearable Self-Charging Power Unit” from the Ministry of Education and Science of the Republic of Kazakhstan.