Insulating SiO2 internally decorated MoS2 flowers as hybrid filler to simultaneously improve breakdown strength and dielectric performance of PVDF-based composites

Nowadays, a great challenge in fabricating dielectric polymer composites lies in how to simultaneously achieve high dielectric constant (ε′)and breakdown strength (Eb). In this paper, silicon oxide (SiO2) nanospheres were internally incorporated into molybdenum disulfide (MoS2) flowers using one-step hydrothermal process. The MoS2@SiO2 hybrids were utilized as fillers in dielectric polymer matrix using solution casting, and the effect of hybrids on dielectric performance was investigated systematically. An optimal composite with 1 wt% MoS2@SiO2 hybrids shows an improved ε′ of [email protected] kHz and high Eb of 486.8 MV/m. The improved dielectric capabilities of polymer composites are ascribed to the improvement of interfacial polarization by MoS2 flower and the suppression of carrier transportation and the charge capture by SiO2. This work broadens the avenue to optimize performance of polymer dielectrics for capacitive energy storage applications by tailoring the interior architectures of hybrid fillers.