The microscopic mechanisms for higher thermoelectric performance of cost competitive rock salt compound Bi2SeS2were investigated. A low doping of Cu as an n-type dopant was conducted in order to optimize the band structure and improve the electrical conductivity. It was revealed that this compound exhibits a Seebeck coefficient higher than 300μVK-1, which sustains above 100μVK-1even with Cu doping, leading to a higher power factor. The microstructural characterizations revealed nano-scale Bi2S3precipitates in the CuxBi2SeS2matrix, beneficial to the lower lattice thermal conductivity that is insensitive to the Cu doping. A thermoelectric figure-of-merit factor ZT of ~0.7 at 450°C in accompanying with the power factor of ~5.36μWcm-1K-2was obtained under the optimized doping level, enabling this environmentally friendly compound interesting for thermoelectric power generation applications.
- Bi SeS 2 2
- Cu doping
- Nano-scale Bi S precipitates 2 3
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)
- Electrical and Electronic Engineering