Dr. Kaviya Somasundaram, Assistant professor, Department of Chemical Engineering, Indian Institute of Science,Bangalore, India

Title: Bio-waste derived nanomaterials for photocatalytic and sensor application

Abstract: The industrial effluents, such as dyes and other commercial colorants, cause severe problems towards environmental protection and have emerged as a focus of environmental remediation efforts. Photocatalytic degradation of pollutants will be appealing if the degradation process is under direct sunlight and in presence of a cost effective catalyst. Similarly, the detection of toxic contaminant in water plays a vital role in the water purification techniques. Metal and semiconductor nanoparticles (NPs) have gained more attention owing to their tunable physical and chemical properties which make them appropriate for the waste water treatment as a photocatalyst and as a substrate for the detection of analytes. The performance of the nanomaterial potentially relay on the size and shape of the particles which can be tuned by the fabrication process. Using biological capping agents for synthesizing/stabilizing NP has been emerged as an attractive alternate over the analogous physical and chemical methods of NP synthesis. Nature provides abundant resources to prepare nanomaterials with novel structures and properties. In this context, we have used the extract of bio-waste to prepare nanomaterials with various size and shape. The bio-waste driven and hierarchical structured semiconductor nanomaterials (ZnO, ZnO-Ag) were used for the photocatalytic degradation of methylene blue under direct sunlight irradiation. The metal (Ag, Au) and luminescent NPs (CdS, ZnS) were utilized as a substrate for SERS (Surface enhanced Raman Scattering), colorimetric and fluorescent sensor for the detection of analytes in aqueous solution. This examination opens up new prospects for preparing highly stable nanomaterials from the bio-waste for various applications.

Keywords: nanoparticles, bio-waste, photocatalyst, degradation, sensor