Synthesis of alkali niobate K1−xNaxNbO3 nanoparticles using a supercritical water flow system

for formation of (a) KNbO3, (b) NaNbO3 and (c) K0.5Na0.5NbO3 nanoparticles using a supercritical water flow system. Conditions: P = 25 MPa, T = 480 °C, H2O flow rate 40 g/min, Nb-sol (0.022 M) flow rate 2 g/min, (Na, K)OH (0.33 M) flow rate 2 g/min, t = 2.2 s.