One-step electrodeposition of free-standing flexible conducting PEDOT derivative film and its electrochemical capacitive and thermoelectric performance

One-pot strategy to fabricate conductive cellulose nanocrystal-polyethylenedioxythiophene nanocomposite: Synthesis mechanism, modulated morphologies and sensor assembly

Simple preparation, good conductivity, and excellent hydrophilicity are in urgent demand due to fast growth of wearable intelligent devices. Cellulose nanocrystal-polyethylenedioxythiophene (CNC-PEDOT) nanocomposites with modulated morphology were prepared through Iron (III) p-toluenesulfonate hydrolysis of commercialized microcrystalline cellulose (MCC) and in situ polymerization of 3,4-ethylenedioxythiophene monomers (EDOT) through one-pot green synthesis, where preparation and modification of CNC were obtained for uses as templates to anchor PEDOT nanoparticles. The resultant CNC-PEDOT nanocomposite gave well-dispersed PEDOT nanoparticles with sheet-like structure on the CNC surface, possessing higher conductivity and improved hydrophilicity or dispersibility. Subsequently, a wearable non-woven fabrics (NWF) sensor was successfully assembled by dipping the conductive CNC-PEDOT, and showed excellent sensing response for multiple signals (subtle deformation from various human activities and temperature). This study provides a feasible and large-scale production of CNC-PEDOT nanocomposites and their applications in wearable flexible sensors and electronic devices.

Benchmarking the Performance of Electropolymerized Poly(3,4-ethylenedioxythiophene) Electrodes for Neural Interfacing

The development of electronics adept at interfacing with the nervous system is an ever-growing effort, leading to discoveries in fundamental neuroscience applied in clinical setting. Highly capacitive and electrochemically stable electronic materials are paramount for these advances. A systematic study is presented where copolymers based on 3,4-ethylenedioxythiophene (EDOT) and its hydroxyl-terminated counterpart (EDOTOH) are electropolymerized in an aqueous solution in the presence of various counter anions and additives. Amongst the conducting materials developed, the copolymer p(EDOT-ran-EDOTOH) doped with perchlorate in the presence of ethylene glycol shows high specific capacitance (105 F g^-1 ), and capacitance retention (85%) over 1000 galvanostatic charge-discharge cycles. A microelectrode array-based on this material is fabricated and primary cortical neurons are cultured therein for several days. The microelectrodes electrically stimulate targeted neuronal networks and record their activity with high signal-to-noise ratio. The stability of charge injection capacity of the material is validated via long-term pulsing experiments. While providing insights on the effect of additives and dopants on the electrochemical performance and operational stability of electropolymerized conducting polymers, this study highlights the importance of high capacitance accompanied with stability to achieve high performance electrodes for biological interfacing.