Development, Dielectric Response, and Functionality of ZnTiO3/BaTiO3/Epoxy Resin Hybrid Nanocomposites

• Published in: Journal of composites science 2024-06, Vol.8 (6), p.225
• Main Authors: Patsidis, Anastasios C, Koufakis, Eleftherios I, Mathioudakis, Georgios N, Vryonis, Orestis, Psarras, Georgios C
• Format: Article
• Language: English
• Subjects: Barium; Barium titanates; Broadband; Charging; Civil engineering; Data analysis; Dielectric properties; Diffraction patterns; energy storing/retrieving; Epoxy resins; Fillers; High temperature; hybrid polymer nanocomposites; Low temperature; Mechanical properties; Nanocomposites; Nanoparticles; Nanostructured materials; Phase transitions; piezoelectric properties; Piezoelectricity; Polymers; relaxations; Scanning electron microscopy; Software; Spectrum analysis; Temperature
• ISSN: 2504-477X
• DOI: 10.3390/jcs8060225

In the present work, hybrid nanocomposites of an epoxy resin reinforced with ZnTiO3 and BaTiO3 nanoparticles, at various filler contents, were fabricated and studied. The successful integration of ceramic nanofillers and the fine distribution of nanoparticles were confirmed via X-ray Diffraction patterns and Scanning Electron Microscopy images, respectively. Dielectric properties and related relaxation phenomena were investigated via Broadband Dielectric Spectroscopy in a wide range of frequencies and temperatures. Data analysis showed that dielectric permittivity increases with filler content, although optimum performance does not correspond to the maximum ZnTiO3 content. Four relaxation processes were observed and attributed to interfacial polarization (IP) (at low frequencies and high temperatures), glass-to-rubber transition (α-relaxation) of the epoxy matrix (at intermediate frequencies and temperatures), and local rearrangements of polar side groups of the macromolecules (β-relaxation) and small flexible groups of the main polymer chain (γ-relaxation) occurring at low temperatures and high frequencies. The ability of hybrid nanocomposites to store and retrieve energy was studied under dc conditions by employing a charging/discharging sequence. The stored and retrieved energy increases with filler content and charging voltage. The optimum ability of energy recovering, shown by the epoxy/7 phr ZnTiO3/7 phr BaTiO3 nanocomposite, ranges between 30 and 50 times more than the matrix, depending on the time instant. The employed nanoparticles induce piezoelectric properties in the nanocomposites, as found by the increase in the piezoelectric coefficient with filler content.