Functionalized bacterial cellulose derivatives and nanocomposites.

Bacterial cellulose (BC) is a fascinating and renewable natural nanomaterial characterized by favorable properties such as remarkable mechanical properties, porosity, water absorbency, moldability, biodegradability and excellent biological affinity. Intensive research and exploration in the past few decades on BC nanomaterials mainly focused on their biosynthetic process to achieve the low-cost preparation and application in medical, food, advanced acoustic diaphragms, and other fields. These investigations have led to the emergence of more diverse potential applications exploiting the functionality of BC nanomaterials. This review gives a summary of construction strategies including biosynthetic modification, chemical modification, and different in situ and ex situ patterns of functionalization for the preparation of advanced BC-based functional nanomaterials. The major studies being directed toward elaborate designs of highly functionalized material systems for many-faceted prospective applications. Simple biosynthetic or chemical modification on BC surface can improve its compatibility with different matrix and expand its utilization in nano-related applications. Moreover, based on the construction strategies of functional nanomaterial system, different guest substrates including small molecules, inorganic nanoparticles or nanowires, and polymers can be incorporated onto the surfaces of BC nanofibers to prepare various functional nanocomposites with outstanding properties, or significantly improved physicochemical, catalytic, optoelectronic, as well as magnetic properties. We focus on the preparation methods, formation mechanisms, and unique performances of the different BC derivatives or BC-based nanocomposites. The special applications of the advanced BC-based functional nanomaterials, such as sensors, photocatalytic nanomaterials, optoelectronic devices, and magnetically responsive membranes are also critically and comprehensively reviewed. Crown