Comparison of solid state synthesis of zinc calcium phosphorous oxide (ZCAP) ceramics under conventional and microwave heating methods

In this study, a weight ratio of 50:30:20 of ZnO:CaO:P2O5 was calcined using microwave and conventional thermal treatment at 800 °C to synthesize zinc oxide calcium phosphorous oxide (ZCAP) ceramics. X-ray diffraction data indicated that microwave synthesized ZCAP ceramics was less crystalline than conventionally synthesized ZCAP. Micro-Raman spectroscopy and FTIR confirmed the presence of ZnO, phosphate and carbonate groups in both heat treatment methods. The reported TGA-DSC results demonstrated that carbonate amount was very less (approx. 0.1%) in microwave synthesized ZCAP while in comparison to carbonate amount was high (approx. 0.69%) in conventionally prepared ZCAP. FESEM image analysis showed that particle sizes were comparatively smaller for microwave synthesized ZCAP than conventionally synthesized ZCAP. Hence, microwave calcinations of ZnO, CaO and P2O5 is a promising method to synthesize ZCAP ceramics compared to conventional thermal calcination treatment.