Designing bio-based photocatalytic platforms: from cellulose hybrids to aerogel-supported systems

Water pollution remains a critical global environmental challenge. According to UNESCO, approximately 80% of wastewater is discharged without adequate treatment, while nearly half the world’s population resides in water-stressed regions. Photocatalysis has emerged as a promising green technology for combating water pollution due to its efficiency, cost-effectiveness, and environmental compatibility. In particular, photocatalytic degradation of organic pollutants, such as dyes, has garnered significant attention.

Our research focuses on the development of novel, sustainable cellulose-supported photocatalysts designed for efficient sunlight-driven degradation of organic contaminants. Cellulose, with its high surface area, reactive functional groups, and compatibility with metal oxides, serves as an effective support material. Additionally, its capacity to mediate electron transfer contributes to reduced charge recombination and enhanced photocatalytic activity. We engineered a range of cellulose-based platforms for the immobilization of metal oxide nanoparticles (CeO₂, ZnO), to create hybrid nanocomposites with improved photocatalytic performance under both UV and visible light. These materials demonstrated effective degradation of a range of hazardous dyes (methyl orange, Congo red, rhodamine B, methylene blue), alongside excellent reusability and operational stability.

Currently, we are designing aerogel-based macroporous matrices as advanced supports for photocatalyst immobilization. These structures aim to increase catalyst loading, improve mass transfer, and prevent leaching. Unlike dense films or submerged polymeric composites, our approach employs floatable substrates positioned at the air–water interface. This configuration maximizes solar light exposure, enhances oxygen availability for radical generation, and significantly boosts overall photocatalytic efficiency.

Our work contributes to the advancement of sustainable water treatment technologies and highlights the potential of biopolymer-based photocatalytic systems for practical environmental remediation applications.

Acknowledgments

This work was supported by a grant of the Ministry of Research, Innovation and Digitization, CNCS -UEFISCDI, project number PN-IV-P1-PCE-2023-1020, within PNCDI IV.