Long-wavelength emissive solid-state carbon dots in nanoporous glass with excellent thermal stability.

Fluorescent solid-state carbon dots have drawn significant attention because of their intriguing optical properties, e.g., broad absorption, stable fluorescence, etc. However, obtaining the fluorescent solid-state carbon dots with a long-wavelength emission is still a challenging problem due to the notorious aggregation-induced quenching problem. In this paper, a technically feasible and low-cost approach for preparing fluorescent solid-state carbon dots is presented. The carbon dots are encapsulated in the nanoporous glass using the solution-phase-doping method. The size of nanoporous glass is tuned to 4.95 nm by regulating the ratio of boron to silicon to match the prepared CDs. Owing to the physical isolation and chemical connection of the -C-O-Si functional groups, the CDs are dispersed uniformly into the nanochannels of nanoporous glass. In this way, the aggregation-induced quenching problem of carbon dots is solved. The experiment results show that the photoluminescence has the excitation-independent emission at 609 nm, i.e., the prepared solid-state carbon dots are with orange fluorescence. More importantly, the solid-state carbon dots preserve orange fluorescence after heating treatment (400 °C) in the ambient atmosphere.