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Transparent conducting Li (0-5 wt%) doped NiO thin films with preferential growth along the (111) plane were deposited onto glass substrates by pyrolytic decomposition of nickel nitrate and lithium chloride precursors at 500 °C in air. The effect of Li concentration on the structural, optical and transport properties of NiO thin films was studied by x-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), spectral transmittance, photoluminescence and linear four-probe resistivity. Activation energies as a function of Li concentration were deduced from the temperature dependent resistivity data measured in the range 300-448 K. The figure of merit was deduced by combining the spectral transmittance and sheet resistance values. The variation in properties of NiO thin film due to Li doping are discussed based on the above results. A dye-sensitized solar cell has also been fabricated for the optimized Li doped NiO thin film and the results are presented.

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ca 2 fe 2 o 5 (cfo) is a potentially viable material for alternate energy applications. incorporation of nitrogen in ca 2 fe 2 o 5 (CFO-N) lattice modifies the optical and electronic properties to its advantage. Here, the electronic band structures of cfo and cfo-n were probed using Ultraviolet photoelectron spectroscopy (UPS) and UV-Visible spectroscopy. The optical bandgap of CFO reduces from 2.21 eV to 2.07 eV on post N incorporation along with a clear shift in the valence band of CFO indicating the occupation of N 2p levels over O 2p in the valence band. Similar effect is also observed in the bandgap of CFO, which is tailored upto 1.43 eV by N + ion implantation. the theoretical bandgaps of cfo and cfo-n were also determined by using the Density functional theory (Dft) calculations. the photoactivity of these CFO and CFO-N was explored by organic effluent degradation under sunlight. The feasibility of utilizing cfo and cfo-n samples for energy storage applications were also investigated through specific capacitance measurements. The specific capacitance of CFO is found to increase to 224.67 Fg −1 upon n incorporation. cfo-n is thus found to exhibit superior optical, catalytic as well as supercapacitor properties over cfo expanding the scope of brownmillerites in energy and environmental applications.Multifunctional brownmillerite Ca 2 Fe 2 O 5 is a promising material for energy and environmental applications such as fuel cells, supercapacitors, batteries, H 2 production and CO 2 capture, attributed mostly to its multifaceted property like those in catalysis and mixed ionic electronic conduction (MIEC) 1-5 . Presence of a visible region bandgap along with its catalytic activity also enables it as a photoactive material and most importantly as material for textile waste water remediation. There is a huge need for industrial waste water purification of the effluents from the textile industries before releasing it to water bodies. A lower cost and energy requirement pushes us to explore more efficient materials which can absorb a larger percentage of incident natural sunlight and make their impact felt on the environment 6-10 . Well known wide band gap semiconductors, such as TiO 2 and ZnO (bandgap > 3 eV), cannot perfectly match the broad ranges of solar radiation emphasizing the need to investigate new materials/composites with narrow bandgap 11 . Quite recently perovskite metal oxides, such as PbTiO 3 (2.75 eV), AgNbO 3 (2.86 eV), SrNbO 3 (1.9 eV), BiFeO 3 (2.1 eV), LaFeO 3 (2.4 eV), LaNiO 3 (2.42 eV) have been found to possess reasonable catalytic efficiency [12][13][14][15][16][17][18][19] . This encourages us to work with novel materials like oxygen deficient perovskites for sunlight-driven photocatalysis.To meet the above objectives, it is desirable to modify such structures with transition metal-N x active sites to enhance the charge transport features and hence the catalytic activity towards remediation of industrial wastewater 20,21 . Recently, Nitrogen-doped layered perovskite K 2 La 2 Ti 3 O 10 was sh...