Preparation of Ba(Cu0.5W0.5)O3-based novel high dielectric ceramics: influence of surfactants

The article investigated the influence of surfactants on the properties of novel Ba(Cu_0.5W_0.5)O₃(BCW)-based high dielectric ceramics prepared using the liquid-phase method, originally employed as a sintering aid. Various surfactants, including polyethylene glycol (PEG), PEG/ citric acid (CA), and CA alone, were added to the tungsten copper barium precursor powders to modulate particle dispersion and surface activity. The treated precursor powders were subsequently subjected to pressing and sintering processes to fabricate ceramic samples, enabling an assessment of the impact of different surfactants on the sintering behavior. Characterization using X-ray diffraction and scanning electron microscopy confirmed that the addition of surfactants remarkably enhanced particle dispersion and promoted interparticle interactions in the tungsten copper barium precursor powders. Furthermore, the incorporation of surfactants effectively increased the density and grain size of the resulting ceramic samples, leading to significant improvements in sintering performance, dielectric properties, and temperature stability. Specifically, the PEG/CA system exhibited a high dielectric constant at 10 Hz (> 10⁵) and a low dielectric loss at 10,000 Hz (= 70), alongside enhanced stability across a broad temperature range. The addition of appropriate surfactants during the liquid-phase preparation of BCW-based high dielectric ceramics substantially enhanced particle dispersion, sintering performance, and temperature stability, thereby providing valuable insights for their potential applications in electronic devices and capacitors.