Copper nickel titanate (CuNiTiO 3 ) and substituted Cu x Ni 1-x TiO 3 (x = 0.3, 0.5, and 0.7) nanoparticles were synthesized via a solution combustion method to investigate their pseudocapacitive energy storage and electrochemical sensing performance. Structural analysis confirmed the formation of a single-phase rhombohedral perovskite with crystallite sizes in the range of 30–36 nm, while morphological studies revealed a porous, agglomerated architecture favorable for electrochemical applications. XPS analysis verified the presence and oxidation states of Cu, Ni, Ti, and O. Electrochemical evaluation in 1 M KCl demonstrated dominant pseudocapacitive behavior, with Cu 0.5 Ni 0.5 TiO 3 exhibiting the highest specific capacitance of 806.21 Fg −1 at 5 mVs −1 , low equivalent series resistance, and excellent cycling stability over 3000 charge–discharge cycles. Capacitive contribution analysis revealed surface-controlled charge storage dominance at higher scan rates. Furthermore, differential pulse voltammetry enabled sensitive detection of Hg 2+ and Sn 2+ ions with limits of detection of 5.95 and 5.41 μM, respectively. The superior electrochemical performance of Cu 0.5 Ni 0.5 TiO 3 highlights its potential as a multifunctional material for advanced energy storage and sensing applications. • Synthesized copper nickel titanate (CuNiTiO 3 and Cu x Ni 1−x TiO 3 ) nanoparticles (x = 0.5, 0.3, 0.7) with crystallite sizes between 30 and 36 nm. • CV, EIS, GCD of CuNiTiO 3 and Cu x Ni 1−x TiO 3 modified carbon paste electrodes were analyzed • Cu 0.5 Ni 0.5 TiO 3 showed the highest specific capacitance of 806.21 F/g at 5 mV/s. • Electrochemical sensing were carried out for Hg 2+ and Sn ions, with a detection limit of 5.95 and 5.41 μM.
Deepa et al. (Wed,) studied this question.