A convenient fluorescent nanoplatform relying on N,B-doped carbon dots to achieve highly selective sensing of dichromate

Abstract

Novel heteroatom-doped carbon dots (APDP-CDs) were synthesized by hydrothermal treatment, and used for dichromate sensing. The average particle size of APDP-CDs was 3.91 nm. They showed absorption peaks at 207 and 290 nm, and fluorescence wavelength was 425 nm when excited at 370 nm. The quantum yield (QY) reached as high as 37.6%, when compared to quinine sulfate as the reference. APDP-CDs showed a linear detection range of 300 nM–1 mM, and the detection limit was found to be 19 nM. Furthermore, APDP-CDs exhibited excellent selectivity and anti-interference to dichromate in the case of different interfering species being present. The quenching process could be attributed to the surface electron transfer between the functional groups and Cr₂O₇²⁻ ions, as well as the inner filter effect. APDP-CDs have been used for actual water sample analysis with satisfactory results, which indicates that the carbon dot-based fluorescence sensor has potential application value.