Plastic Waste‐Derived Carbon Nanotubes Decorated with Mo 2 C, MoO 3 , or MoO 3 /Mo 2 C as Effective Nanocomposite Materials for Supercapacitor Applications

Abstract High‐quality multi‐walled carbon nanotubes (CNTs) were synthesized from low‐density polyethylene (LDPE) waste via a two‐stage process using a CoMo/MgO catalyst. The deposited CNTs were purified and combined with MoO 3 , Mo 2 C, and MoO 3 /Mo 2 C to create 40%MoO 3 @CNTs, 40%Mo 2 C@CNTs, and 20%MoO 3 /20%Mo 2 C@CNTs nanocomposites, which were evaluated for the first time as low‐cost supercapacitor electrodes. Various analytical techniques, including XRD, surface area, TEM, FESEM, EDX, Raman spectroscopy, and TGA, were used to characterize pure CNTs or Mo(x)@CNTs nanocomposites. Raman spectroscopy and TEM results confirmed the successful synthesis of high‐quality CNTs. The XRD and FESEM findings of the Mo(x)@CNTs nanocomposites confirmed the successful formation of highly dispersed MoO 3 and Mo 2 C species in the nanoscale range (24–37 nm) on the surface of CNTs, indicating the effective role of CNTs in enhancing their dispersion. Electrochemical measurements revealed excellent specific capacitance and high cyclic stability (65.4% retention after 2000 cycles) for all nanocomposites. Specific capacitances of 1165.4, 1272.9, and 1211.8 F g −1 at 1 mA g −1 were achieved for MoO 3 @CNTs, Mo 2 C@CNTs, and MoO 3 /Mo 2 C@CNTs, respectively. The enhanced performance of these materials was attributed to their high surface area, porosity, and the synergistic effect between MoO 3 , Mo 2 C, and CNTs. These findings highlight the potential of plastic waste‐derived nanocomposites as cost‐effective supercapacitor electrodes.