<p>This study explores the structural, optical, dielectric, and catalytic properties of BaTiO₃ and its Nd- and Zn-doped derivatives, synthesized via high-energy mechanical milling and solid-state reaction. X-ray diffraction and Raman spectroscopy confirm the retention of the tetragonal perovskite structure with enhanced lattice distortion due to Nd and Zn incorporation. Field emission scanning electron microscopy reveals a systematic reduction in grain size, enhancing the catalytic surface area. UV–Visible spectroscopy demonstrates a significant reduction in the optical bandgap from 3.25&#xa0;eV (pure BaTiO₃) to 2.94&#xa0;eV (co-doped Ba_1-xNd_xTi_1-xZn_xO₃), facilitating visible light absorption. Dielectric studies, modeled using the Havriliak-Negami function, highlight broader and more asymmetric relaxation dynamics, alongside improved thermal stability. Catalytic efficiency was evaluated through the degradation of Rhodamine B dye under ultrasonic vibrations and UV–visible light irradiation, showcasing superior piezo-catalytic and photocatalytic performance in co-doped samples. The results underscore the synergistic effect of Nd and Zn doping, which optimizes charge separation and light absorption, making Ba_1-xNd_xTi_1-xZn_xO₃ a highly efficient catalyst for environmental remediation. These findings pave the way for scalable, multifunctional materials designed for sustainable wastewater treatment and pollution control applications.</p>