(186c) Three-Dimensional Structure Design of Lignin-Derived Photocatalyst for Sustainable Sterilization and Chemical Degradation Under Ambient Conditions

Materials with sterilization and chemical degradation capacity under ambient conditions can efficiently reduce infectious disease incidence rates and toxic chemical exposure, thus benefits public health with broad application potentials. Utilizing renewable energy for sustainable sterilization and degradation is much desired as it reduces the potential secondary contamination. Solar degradation and sterilization present a new route of directing sunlight for persistent chemical pollutant degradation and health-care associated infection prevention with less secondary contamination. As such, photocatalyst working at ambient conditions present a convenient way toward routine contaminant remediation and solar sterilization at normal temperatures. The current photocatalytic system has limited industrial applications due to the requirements of UV radiation, low usage of visible light, fast charge recombination and low transfer efficiency of photo-generated electrons and holes. To overcome the current limitations, we thus designed a green chemical engineering route to utilize a renewable carbon source, lignin, and structural-functionally design a photocatalyst that can be incorporated into diversified material formats and various usages. The novel photocatalyst can be used to rapidly degrade PFAS and other emerging contaminants such as pharmaceutical compounds in water. The photocatalyst can also deactivate macromolecules, kill bacteria. The three-dimensional spherical material potentially has broad applications to promote environmental and public health. Different from most of the photocatalysis driven by UV lights, the presence of the homozygous carbon modified TiO₂ structure contributes to the excellent photodegradation activity with visible light. Ultimately, the resulting C_lignin@H-TiO₂ photocatalyst exhibits superior performance, reaching 100% degradation of atenolol in water, a pharmaceutical compound, within five minutes. At the same time, it efficiently removes approximately 50% of PFOA and kills about 90% of bacteria within three hours. The new lignin based photocatalyst can be broadly used in water treatment to remove and degrade emerging contaminants, routine sterilization to protect public health.