Biotemplating of a Highly Porous Cellulose–Silica Composite from Apium graveolens by a Low-Toxicity Sol–Gel Technique

Abstract

A sol–gel biotemplating technique for the creation of a cellulose–silica composite from Apium graveolens (Pascal celery) has been investigated. The sol–gel biotemplating technique was inspired by pH catalyzed methods used for the creation of hydrogels. This technique did not require the use of highly toxic chemicals or an elevated temperature, and therefore is more environmentally friendly than existing biotemplating techniques. The resulting cellulose–silica composites were geometrically similar to the templated live celery, demonstrating permeability under gas flow at elevated pressure, and the elastic modulus and ultimate compressive strength (UCS) increased by 15.05 × 104% and 3880%, respectively, when compared to live celery. The lack of toxic chemicals or elevated temperature, and the dramatic increase in modulus and UCS provide a low-toxicity alternative to harness the complex and multiscale structure and porosity of organic tissues in bioinspired materials.