Studies on impedance, modulus, and dielectric properties of undoped and Co, V-doped complex perovskite Y2/3Cu3Ti4O12 and Y2/3Cu3Ti3.95Co0.025V0.025O12 ceramic synthesized via novel semi-wet route

Addressing current environmental challenges, a key issue in the ceramic industry is developing bulk electro-ceramic materials through low-cost and eco-friendly synthesis methods. Perovskite oxide has gained significant attention from researchers due to its high dielectric constant and its diverse applications in various fields of daily life. To tackle this, we have synthesized YCTO and YCTCVO, a prominent electro-ceramic material with a structure similar to CaCu₃Ti₄O₁₂ (CCTO), using an environmentally friendly semi-wet route and a readily available, low-cost titanium source. Y_2/3Cu₃Ti₄O₁₂ (YCTO) and Co, V-doped Y_2/3Cu₃Ti₄O₁₂ (YCTCVO) Ceramic were synthesized by semi-wet route. The confirmation of phases in Y_2/3Cu₃Ti₄O₁₂ (YCTO) and Co, V-doped Y_2/3Cu₃Ti₄O₁₂ (YCTCVO) ceramic were determined through X-ray diffraction (XRD) and Le Bail analysis of XRD data which emphasized an occurrence of single-phase formation of YCTO and YCTCVO ceramic along with a minor peak of CuO. Appropriate oxidation state of elements present in YCTCVO was confirmed by X-ray photoelectron microscopy (XPS). The average grain size and particle size of YCTO ceramic from Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) analyses on the respective scale of 4 μm and 0.5 μm were observed through ImageJ software and found to be 1.96 ± 0.50 μm and 0.33 ± 0.05 μm and for YCTCVO to be 4.03 ± 0.50 μm and 0.27 ± 0.05 μm, respectively. The presence of all elements respect to both ceramics were confirmed by Energy-dispersive spectroscopy (EDS) analysis. The average roughness (R_a) and a root mean square roughness (RMS) were calculated to be 0.46 μm (R_a), 0.57 μm (RMS) for YCTO, and 0.51 μm (R_a) and 0.63 μm (RMS) for YCTCVO, respectively. YCTO shows highest dielectric constant 88,395 at 523 K and 100 Hz while it was 1815 at 523 K and 100 Hz for YCTCVO ceramics. The tanδ of the YCTO and YCTCVO was noted approximately 7.0 and 3.6 at 100 Hz and 523 K. It was confirmed from above observations that the higher value of dielectric constant of YCTO ceramic in comparison to that of YCTCVO ceramic which might be due to lower RMS of YCTO ceramic observed through AFM studies, utilized in the application of energy storage devices.