There is a strong dynamic to design tomorrow’s nanomaterials that will be safer both for humans and the environment. The global objective is to develop products made of nanomaterials or nanostructured materials taking into account socio-environmental constraints (exposure and risk) throughout their whole life cycle. In this context, the safer-by-design strategy consists in developing innovative processes to characterize and minimize the materials environmental impact from their synthesis to the end of their lifetime. Nanoparticles are a class of nanomaterials that have received especial attention in this regard. We will present here how the immobilization of TiO2 nanoparticles on cellulose nanocrystals (CNCs) limits their mobility and size related risks. It simultaneously improves their photocatalytic properties in suspension due to an increased dispersability, leading to a lower TiO2 content in the targeted application. The particular case of photocatalytic paints is followed on the complete life cycle. New TiO2 synthesis method leads to the homogeneous covering of CNC by TiO2 nanoparticles mainly in anatase form as demonstrated by X-ray absorption near edge structure (XANES) and with a tunable grafting percentage up to 45 wt. % (determined by ICP-MS). As a result, grafting TiO2 on a biobased material such as nanocellulose in a controlled way increased their photocatalytic efficiency compared to ungrafted TiO2 NPs. This has been demonstrated by the degradation of a water soluble dye. Furthermore, it improved the ageing of the final material and led to a lowered release of larger nanoparticles. Finally, the functionalization of surface-active CNC with the TiO2 allows the scalable degradation of organic pollutants through the preparation of Pickering emulsions and the derived photocatalytic materials.

Safer-by-design approach for the elaboration of versatile nanocellulose-based hybrid particles for photocatalytic applications

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.