Insight into Controllable Preparation of Graphene Quantum Dots by Gaseous Detonation

Background: The gaseous detonation method is a promising method for the rapid and large-scale preparation of graphene quantum dots (GQDs). However, the relationship between detonation parameters and the morphological and optical properties of GQDs remains unclear and needs further investigation. Methods: This study systematically investigates the influence of detonation parameters— specifically, the initial temperature, molar ratio of H2 to O2, and the amount of the precursor (benzoic acid, BA)—on the morphological and optical properties of GQDs. An orthogonal experiment was conducted with initial temperature, H2 to O2 molar ratio, the amount of BA as factors, and particle size, crystallinity, and photoluminescence quantum yield (PLQY) as indicators. Results: Findings indicate that increasing the initial temperature and the molar ratio of H2 to O2 increases the particle size, crystallinity, and PLQY of the GQDs. In contrast, the amount of BA has minimal influence on these properties. Additionally, detonation parameters had no significant effect on the group types, ultraviolet-visible (UV-vis) absorption, and photoluminescence (PL) emission spectra of GQDs. The optimal preparation conditions are when the initial temperature T0 is 393.15 K, the molar ratio of H2 to O2 is 2:1, the amount of BA is 4 g, and the PLQY of the prepared GQDs is maximized. Conclusion: By altering the detonation parameters, the particle size, crystallinity, and PLQY of GQDs can be finely controlled. These findings are highly significant for achieving the controllable preparation of GQDs while providing guidance for the industrial preparation of GQDs with controllable morphologies and optical properties via gaseous detonation. other: Future work will focus on optimizing these parameters to maximize the efficiency and quality of GQD production and exploring the application potential of GQDs in various industrial fields.