Synthesis and characterization of silver/lithium cobalt oxide (Ag/LiCoO2) nanofibers via sol–gel electrospinning

• Silver nanoparticles (NPs) have been produced in aqueous PVP.
• Self-aligned silver NPs in electrospun LiAc/(CoAc)2/PVA/PVP NFs have been produced.
• Ag-doped LiCoO2 NFs have been obtained from the calcinations of as-spun NFs.
• Ag NPs are located at the interlayer of LiCoO2 while some are left in the fiber.
• Ag NPs cannot bond strongly to the fibers, and nanoporous structures are observed.

We report on the preparation and characterization of Ag/LiCoO2 nanofibers (NFs) via the sol–gel electrospinning (ES) technique. Ag nanoparticles (NPs) were produced in an aqueous polyvinyl pyrrolidone (PVP) solution by using AgNO3 precursor. A viscous lithium acetate/cobalt acetate/polyvinylalcohol/water (LiAc/(CoAc)2/PVA/water) solution was prepared separately. A Ag NPs/PVP/water solution was prepared and added to this viscous solution and magnetically stirred to obtain the final homogeneous electrospinning solution. After establishing the proper electrospinning conditions, as-spun precursor Ag/LiAc/Co(Ac)2/PVA/PVP NFs were formed and calcined in air at a temperature of 600 °C for 3 h to form well-crystallized porous Ag/LiCoO2 NFs. Various analytical characterization techniques such as UV–vis, SEM, TEM, TGA, XRD, and XPS were performed to analyze Ag NPs, as-spun and calcined NFs. It was established that Ag NPs in the precursor Ag/LiAc/Co(Ac)2/PVA/PVP NFs are highly self-aligned as a result of the behavior of Ag in the electric field of the electrospinning setup and the interaction of Ag ions with Li and Co ions in the NF. Ag/LiCoO2 NFs exhibit a nanoporous structure compared with un-doped LiCoO2 NFs because the atomic radius of Ag is larger than the radius of Co and Li ion; thus, no substitution between Ag and Li or Ag and Co atoms occurs, and Ag NPs are located at the interlayer of LiCoO2 while some are left in the fiber.