Gamma-irradiation assisted green synthesis of water hyacinth-derived carbon dots for enhanced photoselective film applications

High quantum yield carbon dot (CD) was synthesized from water hyacinth leaves (WH) through ionizing gamma radiation, eliminating the need for heat or chemical treatments. The study investigated the effects of different gamma doses (50, 100, 150 kGy) on the resulting CD's optical properties, particle sizes, and surface chemistry. The 50 kGy dose produced CD (CD50) with a remarkable quantum yield of 48.3 %. Polyvinyl alcohol (PVA)-CD50 composite films demonstrated enhanced root growth in Chinese convolvulus by 19 % and were non-toxic to human cells. These composites also proved effective for food packaging applications, as evidenced by the reduced color changes in strawberries under UV light exposure. This study introduces a green synthesis approach for transforming invasive water hyacinth into a high-value CD, with promising applications in electronics, catalysis, and sensing.