Tuning Interstitials in Fully Dense β-Zn4Sb3 Doubles Single-Leg Thermoelectric Efficiency

Zinc antimonides, particularly the beta-Zn4Sb3 compound, act as prototypes in the early phases of thermoelectric generator (TEG) development. However, their potential applications are constrained by structural instability at elevated temperatures. In this study, introducing a low concentration of aluminum (Al) achieves a highly stable Al-Zn4Sb3, exhibiting an improved peak zT value compared to undoped Zn4Sb3. Notably, a single-leg device utilizing a fully dense Al0.01Zn3.99Sb3 demonstrates an impressive conversion efficiency (eta) of 3% even at a temperature difference (Delta T) of 225 K. This result represents an approximately 200% increase compared with the pristine one. The combination of dilute cationic doping and phase diagram engineering solidifies the potential of Zn4Sb3 as an efficient and sustainable green energy device.

Automated summary

By introducing a low concentration of aluminum (Al) into Zn4Sb3, highly stable Al-Zn4Sb3 was achieved, exhibiting a conversion efficiency of 3% at a temperature difference of 225 K. The combination of dilute cationic doping and phase diagram engineering solidifies the potential of Zn4Sb3 as an efficient and sustainable green energy device.