Fast ion transport for synthesis and stabilization of β-Zn₄Sb₃

Mobile ion-enabled phenomena make β-Zn₄Sb₃ a promising material in terms of the re-entry phase instability behavior, mixed electronic ionic conduction, and thermoelectric performance. Here, we utilize the fast Zn²⁺ migration under a sawtooth waveform electric field and a dynamical growth of 3-dimensional ionic conduction network to achieve ultra-fast synthesis of β-Zn₄Sb₃. Moreover, the interplay between the mobile ions, electric field, and temperature field gives rise to exquisite core-shell crystalline-amorphous microstructures that self-adaptively stabilize β-Zn₄Sb₃. Doping Cd or Ge on the Zn site as steric hindrance further stabilizes β-Zn₄Sb₃ by restricting long-range Zn²⁺ migration and extends the operation temperature range of high thermoelectric performance. These results provide insight into the development of mixed-conduction thermoelectric materials, batteries, and other functional materials.

Dongwang Yang, Xianli Su, Jian He, Yonggao Yan, Jun Li, Hui Bai, Tingting Luo, Yamei Liu, Hao Luo, Yimeng Yu, Jinsong Wu, Qingjie Zhang, Ctirad Uher, Xinfeng Tang