Solvothermally optimizing Ag2Te/Ag2S composites with high thermoelectric performance and plasticity
Min Zhu1, Xiao-Lei Shi2, Meng Li2
1State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, China. qfliu@njtech.edu.cn.
Materials Horizons
|January 13, 2025
Summary
This study developed novel silver chalcogenide composites for improved thermoelectric performance. The Ag2Te/Ag2S materials show enhanced figure of merit (ZT) and superior plasticity compared to pure components.
Area of Science:
- Materials Science
- Solid-State Chemistry
Background:
- Silver-based fast ionic conductors are promising for thermoelectric applications.
- Ag2S offers high plasticity but low electrical conductivity.
- Ag2Te has high electrical conductivity but suffers from high thermal conductivity and poor plasticity.
Purpose of the Study:
- To synthesize Ag2Te/Ag2S composites via a facile solvothermal method.
- To combine the advantageous properties of Ag2S and Ag2Te into a single material.
- To enhance thermoelectric performance and mechanical properties.
Main Methods:
- Solvothermal synthesis of Ag2Te/Ag2S composites.
- Tuning Ag2S and Ag2Te composition to optimize carrier concentration and mobility.
- Characterization of thermoelectric properties (ZT) and mechanical plasticity.
Main Results:
- Achieved a figure of merit (ZT) of ~0.42 at 373 K and ~0.38 at 298 K, surpassing pure Ag2S and Ag2Te.
- Reduced thermal conductivity due to lattice defects scattering phonons.
- Improved plasticity with a bending strain of ~2.5%, significantly higher than pure Ag2Te (~1.2%).
Conclusions:
- Ag2Te/Ag2S composites synthesized via solvothermal methods offer enhanced thermoelectric figure of merit and superior plasticity.
- The composite approach effectively addresses the limitations of individual silver chalcogenides.
- This work provides a pathway for developing advanced composite thermoelectric materials using wet chemical methods.
