Facile synthesis of BCNO quantum dots with applications for ion detection, chemosensor and fingerprint identification

Boron carbon oxynitride quantum dots (BCNO QDs) with blue emission were prepared via the template of SBA-15 (a typical mesoporous silica). A modulated photoluminescence sensor was developed based on the different quenching effects of Cu²⁺ or Hg²⁺ ions on the luminescence intensity of BCNO QDs. The Cu²⁺ or Hg²⁺ ions have an interaction with BCNO QDs due to the electrons transfer between the BCNO and Cu²⁺ or Hg²⁺ ions, and the detection limit of Cu²⁺ or Hg²⁺ ion concentration can be as less as 10 nM. The BCNO-Cr⁶⁺ mixture can be served as a turn-on fluorescent sensor for detecting the ascorbic acid based on the inner filter effect since overlapping of excitation and emission spectra between Cr⁶⁺ ions and BCNO QDs. Moreover, the BCNO QDs can also be applied to fingerprint identification and organic fluorescent films under ultraviolet excitation.