With the massive consumption of energy resources and increasingly severe environmental problems, the development of renewable, environmentally friendly, highly efficient energy conversion and storage devices has become a top priority. Here, a microstructure modulation strategy was proposed to fabricate the oriented regenerated cellulose (ORC) dielectric composites with outstanding mechanical and dielectric properties via a combination of dissolution, crosslinking, stretching, and hot-pressing techniques. ORC films with a stretch ratio of 100 % (ORC-100 film) exhibit a significant increase in displacement values (2.96 µC/cm²), breakdown strength (404.04 MV/m), dielectric constant (14.37 at 1 kHz), and energy density (3.42 J/cm³ at 250 MV/m) as compared to the unstretched regenerated cellulose films. These enhancements are attributed to the anisotropic alignment of cellulose chains and the enhanced crystalline phase of cellulose II, both of which are significantly higher in ORC-100 film. This work offers a feasible and serviceable approach for the development of environmentally friendly cellulose dielectric composites with high performance.

中文翻译：

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具有纳米纤维取向结构的柔性再生纤维素薄膜作为用于介电储能的绿色电介质


随着能源资源的大量消耗和日益严重的环境问题，开发可再生、环保、高效的能源转换和存储设备已成为当务之急。在这里，提出了一种微观结构调制策略，通过结合溶解、交联、拉伸和热压技术来制造具有出色机械和介电性能的定向再生纤维素 （ORC） 介电复合材料。拉伸率为 100 % 的 ORC 薄膜（ORC-100 薄膜）的位移值 （2.96 μC/cm²）、击穿强度 （404.04 MV/m）、介电常数（1 kHz 时为 14.37）和能量密度（250 MV/m 时为 3.42 J/cm³）与未拉伸的再生纤维素薄膜相比。这些增强归因于纤维素链的各向异性排列和纤维素 II 的增强结晶相，这两者在 ORC-100 薄膜中都明显更高。这项工作为开发高性能的环保纤维素介电复合材料提供了一种可行且可行的方法。