Amidst the COVID-19 pandemic, environmental problems such as energy crisis, global warming, and contamination from pathogenic micro-organisms are still prevailed and strongly demanded progress in high-performance energy storing and anti-microbial materials. The nanocomposites are materials that have earned large interest owing to their promising applications for countering global issues related to sustainable energy and a flourishing environment. Here, polypyrrole coated hybrid nanocomposites of multi-walled carbon nanotube and cadmium sulfide quantum dots named MCP were synthesized using facile and low-cost in-situ oxidative polymerization method. Characterization techniques confirmed the synthesis. Electrochemical studies showed that the nanocomposite 1-MCP showed an impressively higher super capacitance behavior in comparison to f-MWCNT, 7-MCP and 5-MCP. The improved performance of the nanocomposites was attributed mainly to the good conductivity of carbon nanotubes and polypyrrole, high surface area, and stability of the carbon nanotubes and the high electrocatalytic activity of the cadmium sulfide quantum dots. Owing to the synergistic effect of MWCNT, CdS, and PPy the synthesized ternary nanocomposite also inhibited the growth and multiplication of tested bacteria such as S. aureus, and E. coli completely within 24 h. On the whole, the assimilated nanocomposite MCP opens promising aspects for the development of upcoming energy storage devices and as an antibacterial agent.