The nitrogen and sulfur co-doped carbon dots(N, S-CDs) with increased luminescence were synthesized by a hydrothermal process in one green pot by using glucose, and a new sulfur-doping source of sodium sulfite was dev...The nitrogen and sulfur co-doped carbon dots(N, S-CDs) with increased luminescence were synthesized by a hydrothermal process in one green pot by using glucose, and a new sulfur-doping source of sodium sulfite was developed.The synergistic effect of the N and S groups was well discussed through the structure analysis of Fourier transform infrared spectra and x-ray photoelectron spectra. The surface states of N, S-CDs embody more complicated functional groups, and S element exists as –SSO3, –C–SO3, and SO-42groups due to the introduction of sodium sulfite. The sulfur-containing groups passivate the surface of the CDs, and the relatively high sulfur groups may reduce the non-radiation centers. The fluorescence is affected by the hydroxyl group of the solvent. The quenching of Fe3+ ion to fluorescence and the sensitivity of fluorescence to p H were also investigated.展开更多
In citric acid-based carbon dots,molecular fluorophore contributes greatly to the fluorescence emission.In this paper,the nitrogen and sulfur co-doped carbon dots(N,S-CDs)were prepared,and an independent sulfur source...In citric acid-based carbon dots,molecular fluorophore contributes greatly to the fluorescence emission.In this paper,the nitrogen and sulfur co-doped carbon dots(N,S-CDs)were prepared,and an independent sulfur source is selected to achieve the doping controllability.The influence of sulfur doping on the molecular fluorophore was systematically studied.The introduction of sulfur atoms may promote the formation of molecular fluorophore due to the increased nitrogen content in CDs.The addition surface states containing sulfur were produced,and S element exists as-SO_(3),and-SO_(4)groups.Appreciate ratio of nitrogen and sulfur sources can improve the fluorescence emission.The photoluminescence quantum yields(PLQY)is increased from 56.4%of the single N-doping CDs to 63.4%of double-doping CDs,which ascribes to the synergistic effect of molecular fluorophores and surface states.The sensitivity of fluorescence to pH response and various metal ions was also explored.展开更多
基金Project by the National Natural Science Foundation of China(Grant Nos.51571085,11805052,and 61705062)the Research Project for Basic and Forefront Technology of Henan Province,China(Grant No.162300410219)the Doctor Foundation of Henan Polytechnic University,China(Grant No.B2014049)
文摘The nitrogen and sulfur co-doped carbon dots(N, S-CDs) with increased luminescence were synthesized by a hydrothermal process in one green pot by using glucose, and a new sulfur-doping source of sodium sulfite was developed.The synergistic effect of the N and S groups was well discussed through the structure analysis of Fourier transform infrared spectra and x-ray photoelectron spectra. The surface states of N, S-CDs embody more complicated functional groups, and S element exists as –SSO3, –C–SO3, and SO-42groups due to the introduction of sodium sulfite. The sulfur-containing groups passivate the surface of the CDs, and the relatively high sulfur groups may reduce the non-radiation centers. The fluorescence is affected by the hydroxyl group of the solvent. The quenching of Fe3+ ion to fluorescence and the sensitivity of fluorescence to p H were also investigated.
基金Project supported by the National Natural Science Foundation of China(Grant No.51571085)the Key Scientific Research Projects of Colleges and Universities in Henan Province,China(Grant No.20A430015).
文摘In citric acid-based carbon dots,molecular fluorophore contributes greatly to the fluorescence emission.In this paper,the nitrogen and sulfur co-doped carbon dots(N,S-CDs)were prepared,and an independent sulfur source is selected to achieve the doping controllability.The influence of sulfur doping on the molecular fluorophore was systematically studied.The introduction of sulfur atoms may promote the formation of molecular fluorophore due to the increased nitrogen content in CDs.The addition surface states containing sulfur were produced,and S element exists as-SO_(3),and-SO_(4)groups.Appreciate ratio of nitrogen and sulfur sources can improve the fluorescence emission.The photoluminescence quantum yields(PLQY)is increased from 56.4%of the single N-doping CDs to 63.4%of double-doping CDs,which ascribes to the synergistic effect of molecular fluorophores and surface states.The sensitivity of fluorescence to pH response and various metal ions was also explored.
