Synthesis and multifunctionality of (CeO2-NiO) nanocomposites synthesized via sonochemical technique

•Successful magnetic nanocomposites (CeO2-NiO) was prepared using sonochemical technique.•The photocatalyst (CeO2-NiO) achieved complete dye degradation (100%).•The two parent oxides are mesoporous while the nanocomposite is microporous.•The parent nanoparticles lead to formation of CNFs while nanocomposite leads to CNTs. CeO2, NiO and their nanocomposite were synthesized using facile sonochemical technique. XRD assure single phase CeO2 and NiO while the nanocomposite consists of the two phases only. CeO2 nanoparticles possess cubic shape, NiO was formed in nanorods, and CeO2 decorated the NiO nanorods in the nanocomposite. The magnetic behavior of the nanocomposite lies between those of the two parents with a ferromagnetic tendency. Metal oxide nanoparticles acted as catalyst in the formation of carbon nanofibers (CNFs), while the nanocomposite leads to the production of carbon nanotubes. The photocatalyst (CeO2-NiO) achieved complete dye degradation (100%) in light for the tested dye at 50 min. The decay products were analyzed using GC mass confirming mineralization of Bb red dye.