A molecular roadmap towards organic donor-acceptor complexes with high-performance thermoelectric response

Abstract As a unique class of molecular electronic materials, organic donor–acceptor complexes now exhibit tantalizing prospect for heat–electricity interconversion. Over the past decades, in design of these materials for thermoelectric applications, consistent efforts have been made to synthesize a...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Wen Shi, Tianqi Deng, Zicong Marvin Wong, Gang Wu, Shuo-Wang Yang
Formato: article
Lenguaje:EN
Publicado: Nature Portfolio 2021
Materias:
Acceso en línea:https://doaj.org/article/526d74523f684835a16e762b334daf89
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:Abstract As a unique class of molecular electronic materials, organic donor–acceptor complexes now exhibit tantalizing prospect for heat–electricity interconversion. Over the past decades, in design of these materials for thermoelectric applications, consistent efforts have been made to synthesize a wide variety of structures and to characterize their properties. However, hitherto, one of the paramount conundrums, namely lack of systematic molecular design principles, has not been addressed yet. Here, based on ab initio calculations, and by comprehensively examining the underlying correlation among thermoelectric power factors, non-intuitive transport processes, and fundamental chemical structures for 13 prototypical organic donor–acceptor complexes, we establish a unified roadmap for rational development of these materials with increased thermoelectric response. We corroborate that the energy levels of frontier molecular orbitals in the isolated donor and acceptor molecules control the charge transfer, electronic property, charge transport, and thermoelectric performance in the solid-state complexes. Our results demonstrate that tailoring a suitable energy-level difference between donor’s highest occupied molecular orbital and acceptor’s lowest unoccupied molecular orbital holds the key to achieving an outstanding power factor. Moreover, we reveal that the charge-transfer-caused Coulomb scattering governs the charge and thermoelectric transport in organic donor–acceptor complexes.