Synthesis and characterization of biomass-derived quantum dots for metalic ion and nanoplastic sensor applications

• Grant number: 23/15333-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: June 01, 2024
• End date: November 30, 2027
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: Altair Benedito Moreira
• Grantee: Vinicius Sarracini Santos
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil

Abstract

Brazil leads global sugarcane production and is the largest exporter of pulp in the world. However, this production generates significant amounts of byproducts such as sugarcane bagasse and Kraft lignin, which are predominantly burned for co-generation of energy, releasing pollutant gases such as CO, CO2, and NOx. By using biomass, there is the possibility of hydrothermal synthesis of nanomaterials known as quantum dots, which have sizes ranging from 1.5 to 10 nm and possess interesting photoluminescent/fluorescent characteristics for various applications. Among the applications, it can be mentioned that these species have the ability for the detection of metal ions by fluorescence quenching, as well as the potential for the detection of nanoplastics, which refers to polymer particles smaller than 1 µm in size. In this project, we propose the synthesis and optimization of quantum dots using sugarcane bagasse and Kraft lignin as precursors, followed by oxidation processes with H2O2 and HNO3, chromatographic separation, and purification by dialysis, characterized by advanced techniques such as transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), aiming to perform experiments for the quantification of Fe3+, Fe2+, Pb2+, Cd2+, Zn2+, Cr3+, Cr6+, Cu2+, and Mn2+ ions, as well as polyethylene, polypropylene, and polystyrene nanoplastics.