Abstract
Dimethylsulfone (DMSO2), a small organic molecule, was observed to induce the alignment of poly(3,4-ethylenedioxythiophene): poly(4-styrenesulfonate) (PEDOT:PSS) via in-situ crystallization in PEDOT:PSS mixture, which was verified by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and atomic force microscopy (AFM). A chemically stable dopant, DMSO2, remarkably raised the electrical conductivity of the PEDOT:PSS film, which was fabricated from pre-mixed solution of PEDOT:PSS and DMSO2, up to 1080 S/cm, and more importantly, such a PEDOT:PSS film showed a long-term humidity stability and it retained near 90% electric conductivity after 60 days, suggesting DMSO2 is promising for an eco-friendly alternative to replace dimethyl sulfoxide (DMSO), ethylene glycol (EG) and various acids dopants that have been widely employed to dope and post-treat PEDOT:PSS. Pairwise interaction energies and free energy of solvation between PEDOT:PSS and DMSO2 were calculated by first-principles and molecular mechanics, respectively, revealing the mechanism of DMSO2 in enhancing the electrical conductivity.
Highlights
In the past few decades, we have witnessed great progress on thermoelectric devices due to its capability to directly convert waste heat into electricity
When dimethyl sulfoxide (DMSO) and inorganic acids are used to dope PEDOT:PSS, a closed encasement or a fume-hood is required for the film preparation and curing process due to toxic and hazardous vapor caused by these volatile solvents
This opens up a new means to fabricate PEDOT:PSS films, which reduces the potential damage to human health and lowers the fabrication cost
Summary
In the past few decades, we have witnessed great progress on thermoelectric devices due to its capability to directly convert waste heat into electricity. The efficiency of the thermoelectric materials is evaluated via the dimensionless figure-of-merit: ZT = S2σ T/κ, where S, σ , T, and κ are Seebeck coefficient, electrical conductivity, thermal conductivity and absolute temperature, respectively Inorganic materials such as Bi2Te3, BiSb, SiGe, and other metal alloys (Han et al, 2014; Zhao and Tan, 2014) were extensively studied, achieving a commendable ZT of about 2 (Culebras et al, 2014b). Post-treatment by immersing the PEDOT:PSS films into EG or acid solution was studied (Culebras et al, 2014a; Park et al, 2014b). The as-prepared doped PEDOT:PSS film annealed on the glass substrate was immersed in solvents, such as water, methanol and ethanol respectively for 1 h at ambient temperature. COMPASS (Condensed-Phase Optimized Molecular Potentials for Atomistic Simulation Studies) force field was used to validate solubility and phase properties of polymers in solution (Sun, 1998; Yildirim et al, 2015)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
