Crafting ecological materials from green resources is posing a significant challenge for the researchers and scientists around the globe and has resulted in the development of nanocellulose materials, which has paved the way for enriching the basic knowledge and many opportunities on developing bio‐based materials. This has augmented the utilization of carbohydrate‐based organic materials and successfully replacing conventional nonrenewable materials. Cellulose nanomaterials (CNMs) belonging to the newer emerging field of nanomaterials are finding increasing interest among the investigators owing to their environmentally sustainable characteristics like biodegradability, biocompatibility, and potential availability in abundance at a cheaper price. The present review article intends to provide a detailed insight about the advancements and various challenges postured in the field of cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs). The article further discusses about different cellulose fiber extraction sources and their methods, purification processes employed, various sample preparation and drying techniques used for CNCs and CNFs. The article also outlines the various characterization methods practiced for scrutinizing CNCs and CNFs when used in polymer matrix composites. Finally, the benefits of using the CNMs in several potential applications such as paper, oil and gas industries, food packaging and structural sectors, conductive ink and water purification areas, medical and printed electronic fields are highlighted in this extensively reviewed article.

中文翻译：

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纤维素纳米晶体和纤维素纳米纤维的全面综述：预处理，制备和表征

用绿色资源制作生态材料对全球的研究人员和科学家构成了巨大挑战，并导致了纳米纤维素材料的开发，这为丰富基础知识和开发生物基材料的机会铺平了道路。这提高了基于碳水化合物的有机材料的利用率，并成功替代了传统的不可再生材料。属于纳米材料新兴领域的纤维素纳米材料（CNMs）由于其环境可持续性特征（如生物降解性，生物相容性和潜在的廉价价格）而在研究人员中引起了越来越多的兴趣。本篇综述文章旨在提供有关纤维素纳米晶体（CNC）和纤维素纳米纤维（CNF）领域中的进步和面临的各种挑战的详细见解。本文进一步讨论了不同的纤维素纤维提取来源及其方法，采用的纯化工艺，用于CNC和CNF的各种样品制备和干燥技术。本文还概述了用于检查聚合物基复合材料中的CNC和CNF的各种表征方法。最后，这篇广泛评论的文章重点介绍了在某些潜在应用中使用CNM的好处，例如造纸，石油和天然气工业，食品包装和结构行业，导电墨水和水净化领域，医疗和印刷电子领域。