Investigation on carrier mobility when comparing nanostructures and bands manipulation
Nanostructuring as an effective strategy to reduce thermal conductivity was well developed to enhance thermoelectric performance in past decades. However, electrical transport properties are always suppressed with nanostructures incorporating into matrix, which finally causes limited increase of thermoelectric performance. To pursue further enhancement in thermoelectric materials beyond nanostructures, the approach of manipulating electronic band structures was revisited to optimize carrier transports through balancing the competitive relationship between carrier mobility and effective mass. In this perspective, we highlight and compare some advanced strategies to optimize electrical transport properties in lead and tin chalcogenides, including nanostructuring, bands manipulation and integrating them. We first summarize recent developments and compare the thermoelectric performance achieved by nanostructuring and bands manipulation, respectively. Then, several strategies to manipulate band structures are introduced and the competitive relationship between carrier mobility and effective mass are comprehensively investigated and revealed. Finally, the importance of elaborately modulating the carrier mobility and effective mass is emphasized, and a discussion of future possible strategies is proposed to aim at further enhancing the thermoelectric performance.
- This article is part of the themed collection: Recent Review Articles