High entropy oxides: promising fillers for high ionic conductivity composite polymer electrolytes

High entropy oxides (HEO) are promising materials for novel applications as they are known to exhibit ultra-high dielectric constants as well as high ionic conductivity when doped with lithium. The combination of these attributes renders HEOs attractive as nano-fillers in composite polymer electrolytes (CPE). We report on the synthesis of (MgCoCuZn)O, (MgCoNiCuZn)O, and Li_x(MgCoNiCuZn)_1-xO utilizing a sol-gel method in combination with high temperature annealing followed by fast quenching to attain single rock salt crystalline order of these HEOs. Nanoparticles are fabricated employing ball milling and different weight loads are incorporated into polymer-salt matrixes. In this talk we will report on ongoing measurements and results on the structural properties of the HEOs and the CPEs as well as ion transport measurements.