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We demonstrate an easy, scalable, and two-step synthesis of macroporous carbon, carbon/TiO2 (cTiO2), carbon/MnO2 (cMnO2), and carbon/TiO2/MnO2 (cTiO2/MnO2) composite thin films for energy storage applications. The direct synthesis of the hybrid films was achieved by spin coating, followed by carbonization. The unique multilayered three-dimensional (3D) pore structure of the film permits the synthesis of carbon/TiO2/MnO2 nanocomposites with enhanced metal-oxide nanoparticle loading up to 50 wt %. The as-synthesized porous carbon thin films were tested for their supercapacitor activity and a maximum specific capacitance ~44 F g-1 was achieved with a film thickness of 350 nm. The as-prepared cTiO2, cMnO2, and cTiO2/MnO2 electrodes exhibit high specific capacitances of 178, 237, and 297 F g-1, respectively, at 5 mV s-1, because of their unique properties with impregnated nanoparticles, and direct fabrication on conductive substrates. This simple scalable coating technique is compatible with the high-speed roll-to-roll manufacturing processes and easily generalized for other carbon/metal oxide composites. We demonstrate an easy, scalable, two-step synthesis method similar to the roll-to-roll process for the synthesis of multilayered of macroporous carbon, carbon/TiO2 (cTiO2), carbon/MnO2 (cMnO2), and carbon/TiO2/MnO2 (cTiO2/MnO2) composite thin films for energy storage applications. [ABSTRACT FROM AUTHOR]

We have fabricated partially alignedfree-standing mesoporous pureanatase TiO2nanofiber mats (TiO2-NF) for photocatalysisby electrospinning on a rotating drum collector using a blend of titaniumisopropoxide (Ti(OiPr)4), with a carrierpolymer, polyvinylpyrrolidone (PVP) in acetic acid and ethanol. Calcinationremoves PVP and generates mesoporous TiO2-NF with fiberdiameters in the range of 25–75 nm by optimizing the electrospinningparameters such as electric field strength, polymer concentration,and flow rate of solution, etc. The band gap energyof TiO2nanofibers from the UV–vis absorption spectrais found to increase with an increase in the calcination temperature,thus allowing band gap engineering for different applications. Thesurface morphology, phase composition, crystallinity, surface area,and porosity of the TiO2-NF are also investigated. We demonstratethe efficient and reusable photocatalytic action of the partiallyaligned pure electrospun TiO2-NF and residual carbon containingTiO2-NF mats with an average fiber diameter ∼40nm in the photocatalytic degradation of a polycyclic aromatic hydrocarbon(PAH) dye, naphthalene. Small carbon residue (2.54%) containing TiO2-NF is found to be about twice as efficient as the pristineTiO2-NF in photodegradation of a PAH dye, but the effectivenessdeclined at higher carbon content. [ABSTRACT FROM AUTHOR]