Figure 2. Observable color change during the synthesis. After 15 min stirring before adding the oxidant (left). One hour after adding the oxidant (centre). End of reaction after 2 hrs (right)

From

Teaching Organic Electronics - Part II: Quick & Easy Synthesis of the (Semi-)Conductive Polymer PEDOT: PSS in a Snap-Cap Vial

Amitabh Banerji, Stephan Kirchmeyer, Klaus Meerholz, Fabian Scharinger

World Journal of Chemical Education. 2019, 7(2), 166-171 doi:10.12691/wjce-7-2-16