A Solution‐Processable Polymer‐Based Thin‐Film Thermoelectric Generator

Abstract

Thermoelectric modules are capable of transforming thermal energy into electrical power. Implementing earth‐abundant and cost‐effective organic materials, they can contribute to an eco‐friendly way of energy production out of low‐grade waste heat and natural heat sources via the Seebeck effect. Moreover, the flexibility of organic materials can allow for adaption to curved surfaces such as the human skin and wearable electronics. Herein, a solution‐processable thermoelectric generator (TEG) using exclusively polymers as active materials is presented. The high‐mobility n‐type polymer poly[[N,N‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5‐(2,2‐bithiophene)] (P(NDI2OD‐T2)) and the widely studied p‐type polymer blend poly(3,4‐ethylene‐dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) are combined into a thin‐film TEG. The presented device design is not limited to this system but is applicable to any pair of organic materials processable from solution and can be easily upscaled to fully flexible devices via, e.g., printing and roll‐to‐roll processing.

Doping Approaches for Organic Semiconductors

“…Further efforts to employ n-type organic semiconductors in p−n leg TEG has been reported by Kluge et al 632 In the TEG, P(NDI2OD-T2) was used as the n-type leg, while PEDOT:PSS treated with ethylene glycol was employed as the p-type leg. To improve the electrical conductivity of the n-type film, the P(NDI2OD-T2) polymer was doped with N-DPBI at different concentrations.…”

Diagnosis of doped conjugated polymer films using hyperspectral imaging

“…[1][2][3][4] In particular, molecular doping of conjugated polymers using solution processable methods is highly suitable for flexible electronic applications including organic thermoelectric and sensor devices. [5][6][7] To realise practical devices based on doped conjugated polymers, the electrical conductivity needs to be significantly increased. 8 The electrical conductivity of doped conjugated polymers is in order of ~10 3 S/cm 9,10 , however, these high performing polymers have poor environmental stability and processability.…”

Solar cell-based hybrid energy harvesters towards sustainability

“…A lot of efforts have been devoted to uncoupling the trade-off relationship between them and then greatly enhancing them simultaneously 104 . Several effective approaches were reported to improve the conversion efficiency of organic thermoelectrics, including organic solvent treatment 93,105−106 , ionic liquids treatment 92,107 , salt solution treatment 108 , and solution doping treatment 109 . To construct highly efficient devices, the utilization of appropriate thermoelectric materials, encompassing both n-type and p-type varieties, is imperative.…”