Electrospinning is an electrostatic process for formation of polymer fibers with nano/microscale diameter from solution. In this study, poly(vinyl pyrrolidone) (PVP) dissolved at 4 wt% concentration in dichloromethane (DCM) containing titanium oxide (TiO2) nanoparticles was used as polymer feed solution for electrospinning under pressurized carbon dioxide (CO2) at temperature of 30 A degrees C, pressure of 5 MPa, and applied voltage of 10-14 kV. Scanning electron microscopy (SEM) revealed that the PVP fibers electrospun with and without TiO2 nanoparticles exhibited the same morphology with hollow structure and average pore diameter of 2-7 mu m. Fourier-transform infrared (FT-IR) spectroscopy revealed that the electrospun PVP fibers had properties similar to the PVP starting material. X-ray photoelectron spectroscopy (XPS) revealed that the TiO2 nanoparticles were present in the residue after thermogravimetric (TG) analysis of electrospun fibers. SEM images of PVP with 25-nm TiO2 nanoparticles, electrospun at 5 MPa and various applied voltages, exhibiting hollow fiber morphology. [GRAPHICS] .