Achieving optimum carrier concentrations in p-doped SnS thermoelectrics

Area of Science:

• Materials Science
• Solid State Physics
• Thermoelectrics

Background:

• Tin(II)sulfide (SnS) is a promising, eco-friendly thermoelectric material.
• Optimizing carrier concentration is crucial for enhancing thermoelectric performance.
• Previous studies explored Ag-doping for SnS optimization.

Purpose of the Study:

• Investigate the effects of Ag-doping and Li-doping on SnS thermoelectric properties.
• Understand the limitations of Li-doping in SnS.
• Provide guidelines for efficient p-type doping of SnS.

Main Methods:

• Experimental doping of SnS with Ag and Li.
• Carrier concentration measurements.
• Thermoelectric power factor analysis.
• Theoretical calculations for defect modeling.

Main Results:

• Ag-doping in a sulfur-rich environment effectively optimizes carrier concentration and power factor.
• Theoretical calculations accurately predict carrier concentration for Ag-doping.
• Li-doping potential is overestimated due to defect complex formation and Li oxidation.
• Oxidation of Li limits its chemical potential in SnS.

Conclusions:

• Ag-doping is a viable strategy for enhancing SnS thermoelectrics.
• Defect chemistry, specifically coupled defects and dopant oxidation, significantly impacts Li-doping efficiency.
• This research offers a comprehensive approach to developing efficient p-doped SnS thermoelectric materials.