Transient C-N-O Configuration-depent Photoluminescence on Graphene Quantum Dots (GQD)

• Main Author: AULIA PERMATASARI (NIM : 10211087), FITRI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/20113
• Institution: Institut Teknologi Bandung

In this research, synthesis of Graphene Quantum Dots (GQD) using hydrothermal method. Ogi, et al. reported that during this method, GQD has transient nature of chemical structure. Therefore, study about C-N-O configuration-depent photoluminscence would be investigated. Precursors are citric acid and urea with concentration of each precursor at 0.0042 mol / L and 0:25 mol / L. The solution was heated using a hydrothermal with continuous temperature rise at specified intervals time. Emission spectrum of the sample was observed for any given time in the heating cycle. The results of the characterization of samples analyzed further to determine the structure and composition of the respective authors - each sample, the particle size and lattice parameters. TEM results showed that the average diameter of the sample was 2.17 nm. Emission spectrum of the sample obtained from PL spectrohotometer samples shows that the peak emission at 460 nm. This value is close to the value estimated energy gap obtained from the modeling approximation effective period. Meanwhile, the components of GQD characterized using XPS and deconvolute according to their constituent structure. The XPS results showed that there was not only concentration change, but also the structure. Based on XPS, we could indicated that N atoms have a important role at photoluminescence. It correlated to N-pyrridinic which change significantly as photoluminescence intensity change. EELS showed that the sampel GQD has interband transition at 5.6 eV.