Coulombic efficiency poly thiophene

Polythiophenes present a multitude of color contrasts. These polymers, with a functional group terminal to a flexible alkyl chain at the 3-position of the ring, are used for many specialized applications. One such candidate of this class is poly(3-[12-(/7-methoxyphenoxy)dodecyl]thiophene [poly(12-MPDDT)], synthesized by Ribeiro et al., which exhibited a deposition charge of ca. 65 mCcm" presented greater stability over a large number of redox cycles (> 1000), a chromatic contrast of 40 % at 725 nm, a Coulombic efficiency of 80 % and good optical memory in the neutral state (E = 0.0 V) [15]. 

An improvement of performance has been obtained with the use of bithiophene as a starting material instead of thiophene for the synthesis of PT. An increase in the specific charge was observed and attributed to the higher regularity in the PT structure [87]. A poly(bithiophene)/lithium solid state cell with poly(ethyleneoxide)/ lithium perchlorate electrolyte was found to have a remarkable stability of 300 cycles at a working temperature of 70°C [88] an initial activation phase was required during cycling, afterwards the coulombic efficiency was 98%. 

Other CPs worth mentioning as having been studied for secondary battery applications include poly(3-butyl-thiophene-co-3-methyl-thiophene) and poly(di-methoxy-phenylene vinylene) [730]. Pandey and Prakash [731] investigated a Zn/poly(indole) secondary battery and found a maximum capacity of 90 Ah/kg with an open circuit potential of 1.45 V and good coulombic efficiency. 

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