The understanding of the interaction between light and complex, random structures is the key for designing and tailoring the optical appearance and performance of many materials that surround us, ranging from everyday consumer products, such as those for personal care, paints, and paper, to light diffusers used in the LED‐lamps and solar cells. Here, it is demonstrated that the light transport in membranes of pure cellulose nanofibrils (CNFs) can be controlled to achieve bright whiteness in structures only a few micrometers thick. This is in contrast to other materials, such as paper, which require hundreds of micrometers to achieve a comparable appearance. The diffusion of light in the CNF membranes is shown to become anomalous by tuning the porosity and morphological features. Considering also their strong mechanical properties and biocompatibility, such white coatings are proposed as a new application for cellulose nanofibrils.

中文翻译：

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白纤维素纳米原纤维膜的异常扩散辅助亮度

了解光与复杂的随机结构之间的相互作用是设计和定制我们周围许多材料的光学外观和性能的关键，从日常消费产品（例如个人护理产品，油漆和纸张）到LED灯和太阳能电池中使用的光扩散器。在此，证明了可以控制纯纤维素纳米原纤维（CNF）在膜中的光传输，从而在只有几微米厚的结构中实现明亮的白度。这与其他材料（例如纸张）形成对比，后者需要数百微米才能获得可比的外观。通过调节孔隙率和形态特征，表明CNF膜中的光扩散变得异常。