Ionic conductivity and conduction mechanism of CsZnPO4 compound

Cesium–zinc orthophosphate (CsZnPO4) was prepared by a solid-state method. X-ray powder diffraction at room temperature confirmed the phase formation of the synthetized compound in the monoclinic system (P21/a space group). Infrared and Raman spectroscopies showed the presence of PO43− anion and its vibrations. Regarding the differential scanning calorimetry, three reversible phase transitions were revealed. The first is of a second-order type located at T1 = 520/503 K (heating/cooling), while the second and the third ones are of a first-order type located at T2 = 544/520 K (heating/cooling) and T3 = 585/577 K (heating/cooling). The detected phase transitions with calorimetric measurements were confirmed by average normalized change (ANC) and electrical conductivity study. The conduction of the studied sample is assured by Cs+ ions’ hopping in tunnels and its mechanism was discussed.