Emerging organic thermoelectric applications from conducting metallopolymers

Abstract

Thermoelectric (TE) materials are emerging as an attractive and promising candidate for solving the energy crisis in which waste heat is efficiently recycled to generate electricity. In order to realize high thermoelectric energy conversion, an ideal TE material should present high electrical conductivity and Seebeck coefficient, but low thermal conductivity. In recent years, conducting coordination polymers have been recognized as new promising organic materials for TE uses, as they bear the advantages of both inorganic and organic materials: proper integration of metal centers helps to enhance the electrical conductivity, while organic backbones are always heat insulators. Herein, a variety of TE metallopolymers are highlighted and their TE properties as well as the related physical factors are discussed in detail. To the best of current knowledge, the highest figure of merit (ZT) value of p-type organic polymers to date has reached 0.42, and by comparison, an Ni-based polymer, poly(Ni-ett) (ett = 1,1,2,2-ethenetetrathiolate), is the only n-type TE material possessing a ZT value comparable to those of PEDOT-based p-type counterparts (PEDOT, poly(3,4-ethylenedioxythiophene)). Based on the current achievements, a promising blueprint is displayed to boost up the further development of metallopolymer-based organic TE materials in the near future.