Improving heat-to-electricity energy conversion with thermoelectric materials by means of electrochemical strategies

Abstract

Compendi d'articlesApproximately 72% of global energy consumption is lost in the form of waste heat. Thermoelectric (TE) devices have gained significant attention owing to their potential to transform heat into electricity, thus contributing to mitigate the present energy crisis. The TE performance is evaluated by the figure of merit zT=S2σT/κ, where S denotes the Seebeck coefficient, σ is the electrical conductivity, T represents the absolute temperature, and κ refers the thermal conductivity. Therefore, obtaining a high zT requires a large power factor (PF=S2σ) together with low κ. This thesis explores the enhancement of the PF in PEDOT:PSS, Ag-ZnO composite, bismuth/antimony telluride alloys, and Sb-doped SnO2 through electrochemical strategies. Upon treatment with 4,4'-bipyridine or LiBF4, PEDOT:PSS exhibited over 3 times PF enhancements. Ag-ZnO combined with BMII ionic liquid resulted in a 1.5-fold increase in the PF. Sb-doped SnO2 functionalized with redox molecules produced 2.5-fold PF improvements.Programa de Doctorat en Tecnologies Industrials i Material