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Updated: May 30, 2026
Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging
Published on: July 19, 2016
Carbogenic nanodots: photoluminescence and room-temperature ferromagnetism
Sachchidanand Srivastava1, Namdeo S Gajbhiye
1Department of Chemistry, Indian Institute of Technology Kanpur, India.
Abstract:
Herein, blue fluorescent carbogenic nanodots (CNDs) with room-temperature ferromagnetism were synthesized by thermal decomposition of organic precursors at different temperatures. Photoluminescence (PL) studies show excitation-wavelength-dependent emission properties and PL excitation (PLE) studies confirm the triplet ground state of carbene at the zigzag edge as the fluorescent center. Room-temperature magnetic studies reveal the ferromagnetic nature of CNDs and temperature-dependent studies show the presence of an antiferromagnetic phase along with a ferromagnetic phase below 50 K. EPR studies reveal the presence of conduction electrons and localized spins with different g factors. Localized spins at zigzag edges are the origin of the unconventional magnetic behavior, whereas exchange coupling between conduction and localized spins are responsible for long-range magnetic ordering.
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