Preparation and characterization of carbon nanodots from natural polysaccharides and its application as photo sensitizer in solar cell

• Main Author: Sta. Ana, Jomar C.
• Format: text
• Language: English
• Published: Animo Repository 2018
• Subjects: Solar cells; Polysaccharides
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/5543
• Institution: De La Salle University

Natural polysaccharides are abundant materials. Their use as precursor for new materials and application is highly desired. This study presents the successful utilization of natural polysaccharide precursors into carbon nanodots (CNDs) using hydrothermal carbonization and its potential as photosensitizer in solar cell. TEM revealed spherical shape of Cladophora cellulose CNDs (5.79 1.60 nm) and crystalline structure (d-spacing of 0.205 1.60 nm indicating graphitic nature. AFM revealed the spherical shape and polydisperse size of the CNDs; Alpha-cellulose CNDs (68.142.3 nm); Cladophora cellulose CNDs (10.0 3.75 nm); cellulose nanocrystal CNDs (76.973.1 nm); chitosan CNDs (18.53.75 nm); and -carrageenan CNDs (57.7 29.7 nm). Difference in size measured for each carbon nanodots prepared from different polysaccharide can be attributed to the properties and size of the initial precursor. FTIR and TOF-SIMs analysis confirmed the presence of hydroxide and carbonyl functional groups that are known to be good anchoring groups for photosensitizer in TiO2. Optical characterization using UV-Vis and Fluorescence Spectroscopy supported the structural and functional group analysis of carbon nanodots suggesting its potential as photosensitizer because it absorbs in the visible region up to 600 nm. The sensitized solar cell fabricated using CNDs as dye replacement showed the potential of CNDs as photosensitizer albeit in lower yield. As compared to the controls.