Cellulose is derived from biomass and is useful in a wide range of applications across society, most notably in paper and cardboard. Nanocellulose is a relatively newly discovered variant of cellulose with much smaller fibril size, leading to unique properties such as high mechanical strength. Meanwhile, electrochemical energy conversion in fuel cells will be a key technology in the development of the hydrogen economy, but new lower cost proton exchange membrane (PEM) materials are needed. Nanocellulose has emerged as a potential candidate for this important application. In this review we summarize scientific developments in the area of cellulosic materials with special emphasis on the proton conductivity, which is the most important parameter for application in PEMs. We cover conventional cellulose and nanostructured cellulose materials, polymer composites or blends, and chemically modified cellulose. These developments are critically reviewed, and we identify interesting trends in the literature data. Finally, we speculate on future directions for this field.

纤维素衍生自生物质，可在整个社会中广泛应用，尤其是在纸和纸板中。纳米纤维素是一种相对较新发现的纤维素变体，其原纤维尺寸小得多，具有独特的性能，例如高机械强度。同时，燃料电池中的电化学能量转换将成为氢经济发展中的关键技术，但是需要新型的低成本质子交换膜（PEM）材料。纳米纤维素已经成为该重要应用的潜在候选者。在这篇综述中，我们总结了纤维素材料领域的科学发展，特别强调了质子传导性，这是在PEM中应用的最重要参数。我们涵盖了常规纤维素和纳米结构纤维素材料，聚合物复合材料或共混物，以及化学改性的纤维素。对这些进展进行了严格审查，我们在文献数据中发现了有趣的趋势。最后，我们推测该领域的未来发展方向。