Fast, direct, low-cost route to scalable, conductive, and multipurpose poly(3,4-ethylenedixoythiophene)-coated plastic electrodes.

Poly(3,4-ethylenedioxythiophene) (PEDOT) films are deposited, using an electroless method, onto flexible plastic poly(ethylene terephthalate) (PET) substrates of approximately 20×6 cm(2). The sheet resistance of a PEDOT-PET film is approximately 600 Ω per square, and the nanoscale conductivity is 0.103 S cm(-1). A plastic electrochromic PEDOT-Prussian blue device is constructed. The device undergoes a color change of pale blue to deep violet-blue reversibly over 1000 cycles, thus demonstrating its use as a light-modulating smart window. The PEDOT-PET film is also used in a quantum dot solar cell, and the resulting photoelectrochemical performance and work function indicate that it is also promising for photovoltaic cells. The high homogeneity of the PEDOT deposit on PET, the optimal balance between conductivity and optical transparency, and the demonstration of its use in an electro-optical device and a solar cell, offer the opportunity to use this electrode material in a variety of low-cost optoelectronic devices.