Research on green synthesis and performance analysis of biomass-derived carbon quantum dots

Biomass-based carbon quantum dots (CQDs) have emerged as promising materials for sustain- able development due to their cost-effectiveness, ease of manufacture, and eco-friendliness. This study investigated the use of sawdust from various wood species— Pinus sylvestris var. mongolica Litv. , Calocedrus macrolepis var. formosana , Cunninghamia lanceolata (Lamb.) Hook. , and Zenia insignis Chun—as carbon sources for CQDs synthesis via a hydrothermal method. Using diverse analytical techniques such as transmission electron microscopy, X-ray diffractometer, ultraviolet-visible spectroscopy, fluorescence spectrophotometry, fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, differences in the properties of CQDs derived from different wood powders were examined. Distinct characteristics were observed among the CQDs obtained from different wood sources. CQDs from coniferous woods showed smaller particle sizes (2.5 nm to 3.0 nm) compared to those from broad-leaf woods (exceeding 15 nm). Unique lattice structures were exclusively found in CQDs from Pinus sylvestris var. mongolica, suggesting an amorphous structure in others. Variations in fluorescence intensity, carbon-to-oxygen ratios, and differing C-O bonding forms were also detected. These distinctions highlight the influence of wood type on CQDs properties, providing insights for tailored design and application. Moreover, this research underscores the potential for utilizing wood waste through CQDs synthesis, contributing to advancements in materials science and promoting sustainable resource utilization. • Coniferous wood CQDs are smaller and uniquely structured compared to broad-leaf wood CQDs. • The study supports converting wood waste into CQDs for sustainable nanomaterial production. • Coniferous wood CQDs are ideal for bioimaging, broad-leaf wood CQDs for stronger fluorescence.