Metal Incorporated Polymeric Nanodots Based Electrode Material for Fluorescent Supercapacitors

In this article, a new class of fluorescent supercapacitor electrode material has been developed by electro-polymerization of Rhodamine b dye in presence of Potassium Ferrocyanide on pencil graphite electrode. The morphology and surface properties of plain polymeric Rhodamine nanodots and Potassium Ferrocyanide incorporated polymeric Rhodamine nanodots were analyzed. Optical and electronic properties of Potassium Ferrocyanide incorporated polymeric Rhodamine b nanodots was found to be superior in comparison with polymeric Rhodamine b nanodots. Potassium Ferrocyanide incorporated polymeric Rhodamine b nanodots shows an enhanced specific conductance (320.0 F/g), and better rate capability 3 to 4 times higher than the plain polymeric Rhodamine b nanodots modified graphite electrodes. The electrochemical activity of the fluorescent Potassium Ferrocyanide doped polymeric Rhodamine b nanodots was found to be easily tailored by changing the concentration of Potassium Ferrocyanide. The 2:1 molar ratio (Potassium Ferrocyanide and Rhodamine b) based polymeric nanodots shows excellent specific capacitance (434.8 F g−1) and fluorescent maxima 580 nm in comparison to other mixing ratios. Potassium Ferrocyanide doped polymeric Rhodamine b nanodots possess excellent rate performance, high energy density of 150.06 Wh kg−1 at a power density of 900 W kg−1, and robust cycling durability, with 99.5% retaining in its specific capacitance even after 6500 cycles. Even after 8 months (40,000 cycles) of testing, the performance of the supercapacitor did not degrade. The excellent performance of the investigated fluorescent nanodots as electrode material could open up the application of supercapacitors to Internet of Things (IoT) applications.