Regenerated Cellulose/NaNbO<sub>3</sub> Nanowire Dielectric Composite Films with Superior Discharge Energy Density and Efficiency
Jiacheng He, Yanan Yin, Menghan Xu, Peng Wang, Zhibo Yang, Quanling Yang, Zhuqun Shi, Chuanxi Xiong
Abstract
Polymer nanocomposites with high energy density hold bright application prospects in advanced electronics and power systems. Traditional dielectric petroleum-based polymers are not biodegradable and renewable. Here, NaNbO3 (NN) nanowires were successfully synthesized via the hydrothermal method and then compounded with environment-friendly regenerated cellulose. The green LiOH/urea aqueous solution was used to dissolve and regenerate cellulose to prepare the regenerated cellulose (RC)/NaNbO3 (NN) dielectric composite films. NN nanowires greatly enhanced the breakdown strength of materials so that the RC/NN composite film with 4 wt % NN nanowires content delivered a desirable energy density of 12.1 J/cm3 at 450 MV/m, which are about 120% and 505% improvements against the neat cellulose (5.5 J/cm3) and the commercially biaxially oriented polypropylene (2 J/cm3), respectively. Concurrently, low dielectric loss and low remnant polarization ensured that the efficiency still reached 80.1%. Moreover, the flexible composite films also stood out in mechanical properties and thermal stability. This work broadens the visions and ideas for natural biomass materials in advanced dielectric capacitors.