Zihang Liu

Thermoelectric materials, with their unique thermoelectric conversion capabilities, show transformative potential across energy, electronics, medicine, and aerospace sectors. Commercial bismuth telluride (Bi2Te3) widely used for room-temperature cooling, is the most well-known example. However, its scarcity and poor mechanical properties limit broader applications, prompting the search for alternative high-performance materials.

Focusing on electrothermal transport mechanisms and thermoelectric materials, Zihang Liu developed a p-type magnesium silver antimonide (MgAgSb) during his graduate studies, which outperforms commercial Bi₂Te₃. He also optimized the new two-step ball-milling process to obtain a pure MgAgSb phase.

In the development of efficient and stable thermoelectric power generation devices, thermoelectric interfacial materials are crucial. Liu and his team proposed a screening strategy for thermoelectric interfacial materials based on phase-equilibrium prediction by density functional theory calculations, targeting candidates with greater chemical complexity.

Their research found that semimetallic magnesium copper antimonide (MgCuSb) serves as a reliable thermoelectric interfacial material for high-performance MgAgSb. The resulting two-pair MgAgSb/Mg3.2Bi1.5Sb0.5 module demonstrated a high conversion efficiency of 9.25% at 300℃, as confirmed by international module-performance round-robin testing.

For cooling applications, they were the first to demonstrate that non-Bi2Te3 thermoelectric materials show great device-cooling performance. At 323 K, the maximum temperature difference and cooling power reached 56.5 K and 3.0 W, respectively.

Moreover, the thermoelectric interfacial material screening strategy has proven broadly applicable to other thermoelectric systems, including zinc antimonide and zirconium cobalt antimonide, addressing a key challenge in the advancement of thermoelectric module development.