Synthesis of cubic-Li₇La₃Zr₂O₁₂ solid electrolyte for all-solid-state lithium-ion batteries via a combination process of induction thermal plasma and calcination

Abstract A combined process enabled the selective synthesis of cubic- and tetragonal-Li 7 La 3 Zr 2 O 12 with calcination for nanoparticles synthesized by induction thermal plasma. The effect of O 2 partial pressure was investigated by adjusting O 2 content within a constant sheath gas flow for plasma-synthesized nanoparticles prepared for calcination. Low O 2 partial pressure led to spherical nanoparticles from the liquid mixture via homogeneous nucleation of ZrO 2 , while high O 2 partial pressure produced irregular, highly aggregated particles from a liquid-solid mixture with homogeneous nucleation of La 2 Zr 2 O 7 . The rapid quenching rate induced amorphous-Li 7 La 3 Zr 2 O 12 , and higher O 2 promoted slight crystallization to cubic-Li 7 La 3 Zr 2 O 12 . This result includes potential for the facile production of ultra-thin cubic-Li 7 La 3 Zr 2 O 12 films suitable for all-solid-state lithium batteries.