Low-temperature hydrothermal–galvanic couple synthesis of BaTiO3 thin films on Ti-coated silicon substrates

Crystalline BaTiO3 films were synthesized on Ti-coated silicon substrates at temperatures below 100 °C using a novel hydrothermal–galvanic couple method: Ti/Si was employed as the working electrode and platinum as the counter electrode without applying any external voltages or currents. Using this method, forming BaTiO3 is possible at temperatures as low as 50 °C over a period of 2 h, which is not possible with the conventional hydrothermal method. The growth rate of BaTiO3 is also much faster when prepared by such a novel method. The growth kinetics can be fitted rather well by a modified Johnson–Mehl–Avrami–Erofe'ev equation. The obtained activation energy for forming BaTiO3 on Ti/Si is 97 ± 9 kJ mol− 1.