Seminar


Department of Chemistry
Indian Institute of Technology Delhi

Carbon nanoparticles as energy devices

Dr. Pradipta Purkayastha
Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, WB, India

Date: October 16th 2017 (Monday)
Time: 4:15 PM
Venue: Committee Room, Chemistry Department, 6th Floor

Fluorescent carbon nanoparticles (CNPs) show potential applications in bioimaging, and non-linear optical processes. Non-cytotoxicity of CNPs has proven them to be excellent alternatives to the considerably more toxic semiconductor quantum dots (QDs). Surface-functionalized CNPs are physicochemically and photochemically stable and non-blinking. CNPs can act as electron donors as well as acceptors, as the case may be in the excited state through photoinduced electron transfer (PET) mechanism. We showed that CNPs accepts electron from dopamine–hydroquinone in acidic medium and donates electron to dopamine–quinone in alkaline medium.1 Moreover, CNPs coated with bilayers of cationic surfactants can control PET between an electron donor and the core of the CNP aggregate. Occurrence of PET from a typical electron donor, dimethylaniline (DMA), to and from CNPs in homogeneous and heterogeneous media shows that the extent of PET between DMA and CNPs can be effectively controlled by varying the thickness of the surfactant shell.2 In addition, PET between electron donor, DMA, and electron acceptor, methyl viologen (MV2+), trapped in reverse micelle environment may be modulated by hydrophobic CNPs.3 Such an arrangement can be used to transfer electrons from a nonpolar to a polar zone controlled by CNPs. The dual electron donor−acceptor property of CNPs helps to relay electrons from one phase to the other.

    References:
  1. S. Mondal, M. Chatti, A. Mallick, P. Purkayastha, Chem. Commun. 2014, 50, 6890.
  2. S. Mondal, T. Das, P. Ghosh, A. Maity, A. Mallick, P. Purkayastha, Mater. Lett. 2015, 141, 252.
  3. S. Mondal, T. Das, A. Maity, S. K. Seth, P. Purkayastha, J. Phys. Chem. C 2015, 119, 13887.


All are cordially invited to attend.
Convener (Seminars)