Green Syntheses of Carbon-based Quantum Dots using Spent Grain from the Brewing Process

M. Demiar, M. Patterson
University of Wisconsin - Stout,
United States

Keywords: carbon quantum dots, spent grain, carbonization, hydrothermal synthesis


The focus of this study is to establish the feasibility of synthesizing carbon quantum dots (CQDs) using spent grain from the brewing process. The spent grain is the primary precursor for carbonization and hydrothermal quantum dot synthesis. This study covers the comparison between the quality, size, and yield of the carbon quantum dots from these two synthesis methods. To date, no studies utilizing spent grain as a precursor for CQDs have been conducted, motivating a study of the quality and yield of CQDs that can be produced. The spent grain was first analyzed using Fourier-transform infrared spectroscopy (FTIR) to verify the molecular bonds present. It was then analyzed via differential scanning calorimetry (DSC) to identify the thermal properties of the precursor. Characterization of the size and quality of the produced carbon quantum dots and the effectiveness of the green synthesis methods were performed using UV-Visible Spectrophotometry (UV-Vis).