Stable Carbon Dots from Microwave-Heated Carbon Nanoparticles Generating Organic Radicals for In Situ Additions
Weixiong Liang,
Buta Singh,
Elton Y. Cao,
Christopher E. Bunker,
William Cannon,
Lauren Petta,
Ping Wang,
Liju Yang,
Li Cao,
Annalise Scorzari,
Ya-Ping Sun
Affiliations
Weixiong Liang
Department of Chemistry, Clemson University, Clemson, SC 29634, USA
Buta Singh
Department of Chemistry, Clemson University, Clemson, SC 29634, USA
Elton Y. Cao
Air Force Research Laboratory, Aerospace Systems Directorate, Wright-Patterson Air Force Base, Dayton, OH 45433, USA
Christopher E. Bunker
Air Force Research Laboratory, Aerospace Systems Directorate, Wright-Patterson Air Force Base, Dayton, OH 45433, USA
William Cannon
Department of Chemistry, Clemson University, Clemson, SC 29634, USA
Lauren Petta
Department of Chemistry, Clemson University, Clemson, SC 29634, USA
Ping Wang
Department of Chemistry, Clemson University, Clemson, SC 29634, USA
Liju Yang
Department of Pharmaceutical Sciences and Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC 27707, USA
Li Cao
Department of Chemical and Materials Engineering, University of Dayton, Dayton, OH 45469, USA
Annalise Scorzari
Department of Chemistry, Clemson University, Clemson, SC 29634, USA
Ya-Ping Sun
Department of Chemistry, Clemson University, Clemson, SC 29634, USA
Carbon dots (CDots) are small carbon nanoparticles with effective surface passivation by organic functionalization. In the reported work, the surface functionalization of preexisting small carbon nanoparticles with N-ethylcarbazole (NEC) was achieved by the NEC radical addition. Due to the major difference in microwave absorption between the carbon nanoparticles and organic species such as NEC, the nanoparticles could be selectively heated via microwave irradiation to enable the hydrogen abstraction in NEC to generate NEC radicals, followed by in situ additions of the radicals to the nanoparticles. The resulting NEC-CDots were characterized by microscopy and spectroscopy techniques including quantitative proton and 13C NMR methods. The optical spectroscopic properties of the dot sample were found to be largely the same as those of CDots from other organic functionalization schemes. The high structural stability of NEC-CDots benefiting from the radical addition functionalization is highlighted and discussed.
