Electric field driven strain and multiferroic properties of Er3+/BiFeO3 nano-catalyst

In this work, we examined the structural, impedance, electro-strain, magnetic properties of Er³⁺/BiFeO₃ nanocatlyst prepared via solid state route. The XRD (X-ray Diffraction) pattern reveals that the BFO has a distorted rhombohedral structure (space group R3c) with average domain size was altered from 38.4 nm to 23.7 nm as Er doping increases on the A-site. The morphological and elemental mapping studies were studied by using FeSEM and EDS. The complex impedance and dielectric investigations were conducted at various temperatures in the frequency range 2 MHz to 10 Hz. The dielectric constant (ε') has been observed to significantly decreases as the frequency increases and to rise as temperature increases. A significant peak-to-peak strain (S^P and S^N) and γ_s (factor of asymmetry) were recorded in the ranges of 0.89–3.32 %, 0.758–3.124 %, and 15.4–34.3 %, correspondingly, with the highest strain memory value (Sm_e%) 0.362. The doping of Er³⁺ ions resulted in an extensive augment in saturation polarization (P_s) from 0.781 to 1.884 μC/cm² and saturation magnetization (M_s) from 0.764 to 3.27 emu/gm, as examined via the P-E hysteresis and M-H hysteresis loops, respectively. Band gap engineering and improved surface reactivity with Er doping led to an improvement in photo-catalytic degradation efficiencies from 64.8 % to 81.4 %.