A facile and eco-friendly synthesis of Mn-doped CaCO3/PMMA nanocomposite for highly efficient supercapacitor in energy storage applications

The Mn-doped CaCO3/PMMA nanocomposite were synthesized using an eco-friendly biomimetic method. This synthesis method is eco-friendly and hot-chemical-free. The current study suggests that instead of using large amounts of chemicals as a source, natural dolomite rock may be used to obtain pure nanocomposites without any impurities for extensive industrial requirements at a lower cost. The products were highly pure and crystalline in nature. The effects on the optical, thermal, and electrochemical properties of nano CaCO3/PMMA:Mn material were studied. The functional group and structural analysis were clearly explained and discussed using FTIR and XRD analyses. The products are in the crystallite size range of 20-40 nm and have a rhombohedral structure. The addition of PMMA to the CaCO3 matrix resulted in the overlapping of multiple color centers, indicating a decrease in the energy gap. Higher thermal stability (837 degrees C) was achieved for CaCO3/PMMA: Mn (0.12 M) nanocomposite than in other literature values. Mn (0.12 M)-doped CaCO3/PMMA has a high specific capacitance, good rate capability, and outstanding cyclic stability. The specific capacitance of CaCO3/PMMA: Mn (0.12 M) nanocomposite was higher than other literature values. These techniques suggest that Mn doping and PMMA matrix decoration can enhance the electrochemical performance of CaCO3 electrolytes. The cyclic stability of CaCO3/PMMA: Mn (0.12 M) nanocomposite after 2000 cycles at 5 Ag- 1 showed better cycle endurance, with a high retention of 93.2%.