Optimizing Sn Doping in Zn₄Sb₃ Thin Films: Insights into Processing and Electrical Performance

Area of Science:

• Materials Science
• Solid State Physics
• Energy Harvesting

Background:

• Beta-Zn4Sb3 is an environmentally friendly thermoelectric material suitable for mid-temperature applications.
• Phase instability during fabrication is a major challenge, degrading thermoelectric performance.
• Developing stable thermoelectric materials is crucial for renewable energy technologies.

Purpose of the Study:

• To optimize beta-Zn4Sb3 thin films for enhanced thermoelectric performance.
• To investigate the effect of controlled tin (Sn) doping on phase stability and thermoelectric properties.
• To establish a pathway for fabricating high-quality thermoelectric thin films.

Main Methods:

• Ion beam-assisted deposition was used to create Sn-doped beta-Zn4Sb3 thin films.
• Precise control of Sn concentration (0.97%) was employed to stabilize the beta-phase.
• Thermoelectric properties, carrier mobility, and structural stability were comprehensively analyzed.

Main Results:

• Controlled Sn doping at 0.97% successfully preserved the pure beta-Zn4Sb3 phase.
• A maximum power factor of 1.4 mW m⁻¹ K⁻² was achieved at 573 K, a 60% improvement over undoped films.
• Dilute Sn doping enhanced carrier mobility and structural stability, preventing phase transitions to ZnSb.

Conclusions:

• Precise doping and processing control are essential for stabilizing the beta-phase of Zn4Sb3.
• Sn doping offers a viable strategy for fabricating high-performance thermoelectric thin films.
• This research contributes to the development of scalable and efficient energy harvesting technologies.