Substrate material dependant structural, morphological and electrochemical behavior of spray pyrolysed titanium oxide thin films via partially aqueous route

Abstract

By using 0.04 M partially aqueous solution of 1-propanol in double distilled water, thin films of TiO2 has been prepared on different conducting substrates such as stainless steel (SS), copper (Cu) and fluorine doped tin oxide (FTO) by using ultrasonic spray pyrolysis. Decomposition was carried out at 723 K, 10 cc/min spray rate. The structural, morphological and electrochemical properties of the thin films have been studied. Sample show tetragonal crystal structure with rutile as prominent phase. The novel nano-bricks like morphology was observed by scanning electron microscopy and transmission electron microscopy for the sample deposited on SS substrate. In electrochemical study, all deposited samples show pseudocapacitive behavior as observed from cyclic voltametry. The highest specific capacitance values observed from cyclic voltammetery, in 1 M KOH for the electrode deposited on SS, Cu and FTO substrates are 706.87, 5150.00 and 90.22 F/g respectively. From the charge discharge behavior, the observed highest values of electrochemical parameters such as specific energy 82.77 Wh/kg, specific power 41.25 kW/kg and efficiency (η) 93.17% respectively. Impedance study was carried out for the optimized electrode in the frequency range 1 mHz–1 MHz exhibits moderate internal resistance 3.896 Ω.