• Mondal, Jayanta

Abstract

<jats:p>The present work is focused on the fabrication of manganese dioxide/carbon dots (MnO<jats:sub>2</jats:sub>/CDs) nanocomposites at room temperature <jats:italic>in situ</jats:italic> co-participation method in an aqueous medium and characterized. Our study showed that the concentration of CDs controls the morphologyof MnO<jats:sub>2</jats:sub>/CDs nanocomposite and also acted as a reducing agent to convert potassium permanganate (KMnO<jats:sub>4</jats:sub>) to MnO<jats:sub>2</jats:sub>. Subsequently, nanoflowers, quasi-spherical particles, broken, and interconnected chain type of morphology was observed by adding dispersion of 0.5,1.0, 1.5, and 2.0 ml CDs in acetone to 1 mmol KMnO<jats:sub>4</jats:sub> aqueous solution in the corresponding MnO<jats:sub>2</jats:sub>/CDs-0.5, MnO<jats:sub>2</jats:sub>/CDs-1.0, MnO<jats:sub>2</jats:sub>/CDs-1.5, and MnO<jats:sub>2</jats:sub>/CDs-2.0 composites, respectively. A plausible mechanism on the transformation of morphology ofMnO<jats:sub>2</jats:sub>/CDs with CDs concentration is also provided. Further, the present work also focused for the first time on the application in the electromagnetic interference (EMI) shielding of MnO<jats:sub>2</jats:sub>/CD nanocomposites due to the high dielectric and conductivity. Interestingly, MnO<jats:sub>2</jats:sub>/CDs-2.0(nanochains) exhibited the highest total EMI shielding efficiency (SE<jats:sub>T</jats:sub>) of ~39.4 dB following reflection as dominant shielding mechanism due to the high aspect ratio, highest conductivity, high dielectric loss, and impendence mismatch.</jats:p>

Topics

• nanocomposite
• impedance spectroscopy
• morphology
• dispersion
• Carbon
• Potassium
• Manganese