Improved Performance of Organic Thermoelectric Generators Through Interfacial Energetics

The interfacial energetics are known to play a crucial role in organic diodes, transistors, and sensors. Designing the metal-organic interface has been a tool to optimize the performance of organic (opto)electronic devices, but this is not reported for organic thermoelectrics. In this work, it is de...

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Detalles Bibliográficos
Autores: Petsagkourakis, Ioannis, Riera Galindo, Sergi, Ruoko, Tero-Petri, Strakosas, X, Pavlopoulou, Eleni, Liu, X, Braun, S, Kroon, Renee, Kim, N, Lienemann, Samuel, Gueskine, V, Hadziioannou, G, Berggren, M, Fahlman, Mats, Fabiano, Simone, Tybrandt, Klas, Crispin, Xavier
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/335488
Acceso en línea:http://hdl.handle.net/10261/335488
https://api.elsevier.com/content/abstract/scopus_id/85156113926
Access Level:acceso abierto
Palabra clave:Seebeck coefficient
Interface
Organic electronics
Organic thermoelectric generator
Polymer thermoelectrics
Thermoelectric
Descripción
Sumario:The interfacial energetics are known to play a crucial role in organic diodes, transistors, and sensors. Designing the metal-organic interface has been a tool to optimize the performance of organic (opto)electronic devices, but this is not reported for organic thermoelectrics. In this work, it is demonstrated that the electrical power of organic thermoelectric generators (OTEGs) is also strongly dependent on the metal-organic interfacial energetics. Without changing the thermoelectric figure of merit (ZT) of polythiophene-based conducting polymers, the generated power of an OTEG can vary by three orders of magnitude simply by tuning the work function of the metal contact to reach above 1000 µW cm-2 . The effective Seebeck coefficient (Seff ) of a metal/polymer/metal single leg OTEG includes an interfacial contribution (Vinter /ΔT) in addition to the intrinsic bulk Seebeck coefficient of the polythiophenes, such that Seff  = S + Vinter /ΔT varies from 22.7 µV K-1 [9.4 µV K-1 ] with Al to 50.5 µV K-1 [26.3 µV K-1 ] with Pt for poly(3,4-ethylenedioxythiophene):p-toluenesulfonate [poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)]. Spectroscopic techniques are used to reveal a redox interfacial reaction affecting locally the doping level of the polymer at the vicinity of the metal-organic interface and conclude that the energetics at the metal-polymer interface provides a new strategy to enhance the performance of OTEGs.