Yttria activated lanthanum -barium titanate ceramic electrode for fast charging supercapacitor applications

Abstract

Lanthanum oxide (La2O3) and Yttria (Y2O3) activated lanthanum-barium-titanate Ba(60-x)Ti(40-y)LaxYyO3 (BTLa10Y10), nanoceramics were investigated for structural, morphological, dielectric and electrochemical properties. These ceramics were prepared through solid-state reaction followed by calcination at 1100 °C for 8 h and sintering temperature at 1275 °C for 6 h. XRD pattern of BTLa10Y10 exposed to a change of crystal structure from rhombohedral (R) to tetragonal (T) after the doping of Y2O3. A feeble FT-IR band at 539 cm−1 was associated to La–O bending vibrations in BTLa10Y10 ceramics. Raman spectral bands at 155 and 214 cm−1 are associated with the R phase, while the modes at 528 and 729 cm−1 are related to the T phase. The clustered particles with a typical grain size of 298 nm, and the pore size of 28.72 (BTLa10) and 27.18 nm (BTLa10Y10) were attained. The Nyquist plot of BTLa10Y10 exhibited two overlapping semicircles at higher frequencies, indicating two relaxation processes. Moreover, the highest specific capacitances and energy densities were reported for BTLa10Y10 due to its pseudocapacitive nature as 3.1106 F/g and 1.5553 W h/Kg, respectively. The electrochemical impedance spectroscopy proved that the linear behaviour of the profile indicates a fast electron response of BTLa10Y10 ceramics are significant for fast charging supercapacitor applications.