High sintering activity NaNbO3 powder synthesis via the polyacrylamide gel method and fabrication of a NaNbO3 ceramic at lower temperature

NaNbO3 powder was synthesized via the polyacrylamide gel method, growth behaviors and associated morphology were discussed. The calcined NaNbO3 powder at 565 degrees C possess cubic and long columnar morphology which are NaNbO3 and Na/Nb/F or Na/Nb/F/O compounds, respectively. According to XRD and SEM, as calcined temperature raised, the amount of F in Na/Nb/F or Na/Nb/F/O compounds gradually reduced, long columnar compounds resolved into cubic NaNbO3. These changes made the NaNbO3 powder which calcined at 565 degrees C obtain highly sintering activity, dense NaNbO3 ceramic can sintering at 1200 degrees C. NaNbO3 ceramic densification was caused by the large ionic radius O2- replaced the small ionic radius F- during the calcining process. Compared with the solid-state re -action method, the sintering temperature of NaNbO3 ceramic was be reduced in this work, which contribute for low-temperature sintering technical of NaNbO3 ceramics. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).