Thermoelectric Materials: A Brief Historical Survey from Metal Junctions and Inorganic Semiconductors to Organic Polymers

Abstract

Dedicated to the memory of Prof. Michael Bendikov and his many contributions to the field of organic electronics

A review of carrier thermoelectric-transport theory in organic semiconductors

“…Organic semiconductors are mainly based on earth-abundant elements, that is, C, H, and O. Although compared with inorganic thermoelectric materials, the organic semiconductors still exhibit a lower ZT (approximately 0.5) so far [23][24][25], there are several more advantages in organic semiconductors instead of inorganic materials [26][27][28][29], for example, the non scarcity of raw materials, the non toxicity, and the large area applications, etc. Due to these excellent properties, along with their specific charge thermoelectric transport properties, organic semiconductors are of growing interest in some cases unique for various applications, particularly for thermoelectric 5 / 56 theoretical description of thermoelectric technology in organic semiconductors [45,52,53], however, the current reviews inclined to the scope of organic crystal materials, as well as the thermoelectric figure of merit.…”

Development of Perovskite-Type Materials for Thermoelectric Application

“…Materials such as organic [5,6,24,25,26,27,28,29,30,31,32], hybrid perovskites [33,34,35] and the group V chalcogenides [3,7,10,11,12,36] are suitable for TE application at the near-room-temperature range. In addition, TE materials—such as the group IV chalcogenides [10,11,20,36], group III-V compounds [10,17,36], group IV-based materials [7,10,12,36], half-Heusler alloys [3,7,9,11], skutterudites [3,11,37], Zintl compounds [3,9,12,37], and clathrates [9,11]—are applicable at the middle temperature (about 400–900 K) range.…”

“…For example, NaCo 2 O 4 was reported to have an in-plane S of 100 µV·K −1 and σ of 5000 S·cm −1 at 300 K [49], Bi 2.2 Sr 1.8 Co 2 O 9 achieved a ZT value of 0.19 at 973 K with S of ~150 µV·K −1 , σ of ~82 S·cm −1 and κ of ~0.9 W·m −1 ·K −1 [50], Ca 3 Co 4 O 9 showed a S of ~125 µV·K −1 and σ of ~28 S·cm −1 at 300 K [51], Zn 0.96 Al 0.02 Ga 0.02 O reached a ZT value 0.65 at 1247 K with S of 230 µV·K −1 , σ of ~400 S·cm −1 and κ of 5 W·m −1 ·K −1 because of a bulk nanocomposite structure [52]. In the past decade, many efforts have been put into the investigation of organic thermoelectric materials [25,26,27,28,29]. Moreover, the hybrid perovskites started to draw attention for TE application [35].…”

Toward Stretchable Self‐Powered Sensors Based on the Thermoelectric Response of PEDOT:PSS/Polyurethane Blends

“…In the case of TE technology, conventional systems have been considered as a power source for integrated sensors of pressure, corrosion, heat flow, vibration, heart rate, and other stimuli . The utilization of conjugated polymers as the active component of a TE device is a relatively recent concept, but it is rather attractive where flexibility is needed, enabling a new generation of novel, low‐cost, low‐powered wearable, or even remote, sensors. There are many desirable attributes driving the investigation of polymer TE materials, such as low toxicity, ubiquity, and abundance of constitutive elements, as well as ease in processing by various established coating or printing techniques.…”