Highly Photoluminescent Carbon Dots Derived from Egg White: Facile and Green Synthesis, Photoluminescence Properties, and Multiple Applications

Carbon dots, which are superior fluorescent nanomaterials with low photobleaching, low toxicity, excellent biocompatibility, and low environmental hazard, have presented exciting opportunities in many fields. However, a better strategy to synthesize fluorescent carbon dots with high quantum yield and further developing their potential applications is still needed. Herein, a one-step hydrothermal strategy was proposed to prepare carbon dots from egg white. The as-prepared CDs, with a diameter of 2.1 nm, were well-dispersed in aqueous solution and showed excellent pH stability. During the hydrothermal reaction, the carbonization, N-doping, and surface functionalization were realized at the same time. With a high quantum yield of 61%, the CDs were used as a probe for detecting metal ions and in living cell imaging. Additionally, multifunctional nanocomposites were also prepared with novel thermosensitive photo-luminescent properties.