Silver selenide (Ag₂Se) has emerged as a promising material for near room-temperature energy harvesting via thermoelectric conversion. With its lower toxicity, greater abundance, and superior mechanical stability, Ag₂Se offers a sustainable alternative to conventional bismuth telluride-based compounds. This presentation will provide an overview of recent advancements in our research group for bulk silver selenide-based thermoelectric materials. Numerous strategies have been employed to enhance the thermoelectric efficiency of bulk Ag₂Se, including doping, carrier concentration control, stoichiometry optimization, and nanostructuring. In our research group, we have employed the cold sintering process (CSP) to consolidate bulk Ag₂Se, offering a fast and efficient method to fabricate materials with improved thermoelectric properties. By utilizing CSP, we have engineered multi - scale hierarchical structures in Ag₂Se, facilitating wide - range phonon scattering and significantly reducing thermal conductivity. Through careful tuning of CSP parameters, we have manipulated carrier concentration via defect engineering, leading to enhanced transport properties and power factors. These advancements have yielded dimensionless figure-of-merit (ZT) values exceeding unity, with an average ZT of approximately 1.0 from room temperature to around 400 K, positioning bulk Ag₂Se as a viable material for thermoelectric power generation in room-temperature energy harvesting applications.

Professor Supree Pinitsoontorn

Director of the Institute of Nanomaterials Research and Innovation for Energy (IN-RIE),

Head of the Department of Physics, Faculty of Science,

Khon Kaen University, Khon Kaen 40002 THAILAND

Achievements / Awards

• Outstanding Research Award from National Research Council of Thailand

• DPST Hall of Fame 2023 from Institute for the Promotion of Teaching Science and Technology

• Honorary Sarasin Award from Khon Kaen University for Outstanding Researcher

• Study UK Alumni Awards (Science and Sustainability Award)

•Outstanding Research Award from National Research Council of Thailand

•Gold Medal Award from Khon Kaen University for Outstanding Researcher