We report a facile way to synthesize
polythiophenes carrying pendant
2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) radicals, here called
PTATs, by electropolymerization in boron trifluoride diethyl etherate
(BFEE). The spacing between the TEMPO radical and the polythiophene
backbone is varied by an alkyl spacer (n = 2, 4,
6), and the electronic and electrochemical properties are examined
using UV–vis spectroscopy, cyclic voltammetry, and electrochemical
impedance spectroscopy. Film morphologies are also studied via scanning
electron microscopy (SEM) and atomic force microscopy (AFM), which
show that the longer octyl chain placed between thiophene and TEMPO
effectively suppresses aggregation. The highest conductivity and electroactivity
are observed for n = 4 and n = 6,
respectively. Such morphology differences provide an opportunity to
better understand the charge transport and energy storage properties
in electronic materials.