*2.2. Synthesis of Polypyrrole (PPy)*

PPy was synthesized by using a pyrrole monomer via inverse emulsion polymerization. The procedure was carried out in a three-necked round bottom flask holding 35 mL toluene and 10 mL 2-propanol that was stirred for 15 min. After that, 200 μL of pyrrole was added and stirred for another 15 min, followed by drop wise addition of 0.5 mL of DBSA and 0.303 g of benzoyl peroxide (dissolved in 5 mL of water) to the reaction mixture. To get the precipitate, the mixture was vigorously stirred for 24 h. The precipitate was washed three times with distilled water and 50 mL of acetone to separate the pure product that was dried in an oven at 50 ◦C for 24 h. The representative procedure of the synthesis of polypyrrole has been sketched in Figure 1.
