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Ternary perovskite oxides are potential candidates as stand-in electron transport materials to replace the conventional binary TiO2 in dye-sensitized solar cells (DSSCs). Here, we report the synthesis of nanostructured perovskite ternary oxide BaSnO3 (BSO) photo anode doped with lanthanum (LBSO) using a facile peroxide route and demonstrate the alternative efficient electron transport layers for DSSCs. A double surface treatment method with TiCl4 was initially applied to the transparent conducting layer (TCL) to enhance the performance of DSSCs based on La-doped BaSnO3. The DSSCs containing the pre-treated (TCL/LBSO3) exhibited better power conversion efficiency (PCE) of 4.37%. Furthermore, the DSSC device assembled with pre and post (TCL/LBSO3/TCL) surface treated film exhibited the highest PCE of 5.96%, which is 60% higher than DSSC with undoped, pre and post (TCL/BSO/TCL) surface treated film (3.71%). Hence, pre and post-treated LBSO3 can be considered a promising alternative ETL layer for DSSCs due to its superior charge collection efficiency and reduced recombination rates confirmed by impedance analysis. [ABSTRACT FROM AUTHOR]

Phase pure NdFeO3 has been achieved using high energy ball milling of oxide precursors with subsequent sintering. It is established that structural arrangement of NdFeO3 regulates the multifunctional feature of the material. Rietveld refinement of the room temperature X-ray diffraction pattern shows that the Fe-O-Fe bond angle significantly favors the super exchange interaction, which is predominantly antiferromagnetic in nature. Magnetization measurement illustrates antiferromagnetic behaviour with a weak ferromagnetic component caused by the canted nature of the Fe3+ spins at room temperature. Absorption bands in the visible ambit, apparent from the UV-Vis diffuse reflectance studies, is found due to the crystal ligand field of octahedral oxygen environment of Fe3+ ions. The direct band gap is estimated to be 2.39 eV from the diffuse reflectance spectrum. The lossy natured ferroelectric loop having a maximum polarization of 0.23 μC/cm² at room temperature is found to be driven by the non-collinear magnetic structure with reverse Dzyaloshinskii-Moriya effect. Magnetic field has influence on the dielectric constant as evident from the impedance spectroscopy, indicating the strong coupling between ferroelectric and the magnetic structure of NdFeO3. [ABSTRACT FROM AUTHOR]

Today is the era of Internet and networks applications. So the Information Security has been very important issue in data communication. Any loss to information can prove to be great loss to the organization. Encryption has come up as a solution, and plays a vital role in information security system. Many techniques are needed to protect the shared data. The present work focus on cryptography to secure the data while transmitting in the network. First the data which is to be transmitted from sender to receiver in the network must be encrypted using the encryption algorithms. Secondly, by using decryption techniques the receiver can view the original data. This paper provides a in depth comparison of five most common and used symmetric and asymmetric key algorithms: DES, 3DES, AES, RSA and MD5 algorithms and comparison has made based on their performance and time of encryption and decryption, block size, key size, and breakage of encryption/decryption time, throughput. [ABSTRACT FROM AUTHOR]

Highlights: [•] Undoped film was oriented along the 〈0 k 0〉 direction. [•] Mo 3d 5/2 and 3d 3/2 doublet caused by spin–orbit coupling are resolved with a splitting of 3.1eV. [•] Direct and indirect band gaps showed red shift with ‘Li’ doping compared to undoped film. [•] Intensity of the green photoluminescence emission spectra is quenched with ‘Li’ concentration. [•] Dye sensitized solar cell is fabricated using undoped MoO3 thin film as photoanode. [ABSTRACT FROM AUTHOR]

The electrical resistivity and magnetization of half-metallic/superconducting La0.7Sr0.3MnO3=Bi2Sr2CaCu2O8 (LSMO/Bi-2212) heterostructures are investigated with the thickness of Bi-2212 top layer fixed at 50 nm and that of the LSMO underlayer (t) being 40, 80 and 160 nm. Both the normal state resistivity ρ(290 K) and the superconducting transition width (δTC) increase with increasing t. On the other hand, the superconducting transition onset temperature (Tcon) of Bi-2212 monotonically decreases with increasing t, which is attributed to pair breaking via the polarized spins from the ferromagnetic LSMO due to strengthening of the magnetization. However, the rate of reduction of Tcon in Bi-2212 with respect to the thickness of LSMO is found to be much less in LSMO(t)/Bi-2212 compared with that of YBCO in the analogous system PCMO(t)/YBCO. From the qualitative analysis of the electrical and magnetic data we conclude that growing domains enhancing the magnetization is the reason for the thickness-dependent suppression of superconductivity in LSMO(t)/Bi-2212 bi-layers. [ABSTRACT FROM AUTHOR]

Abstract: The effect of Li (0–5wt%) doping on the properties of WO3 thin films deposited using an automated homemade spray pyrolysis unit is studied. Change in structural and optical properties is observed on doping with Li. The XRD patterns shows that undoped WO3 film has an orthorhombic phase while the Li (1–5wt%) doped WO3 films have tetragonal phase. The SEM and AFM images confirm relatively smooth surface of Li doped WO3 films compared to undoped WO3 film. Transmission spectra reveal that the transparency of the Li-doped films is much greater than that of undoped film. From the transmission data, the direct, indirect bandgap and phonon energies were calculated. Room temperature photoluminescence spectra showed pronounced blue emission on doping with Li. [Copyright &y& Elsevier]

Abstract: Studies on spray deposited transparent conducting Li doped SnO2 thin films are scarce. Li (0 to 5 wt.%) doped SnO2 thin films spray deposited onto glass substrates at 773 K in air from chloride precursors were studied for their structural, optical and temperature dependent electrical behaviors. X-ray diffraction patterns indicated single phase with polycrystalline nature. Systematic variation in surface morphology on Li doping was examined by scanning electron microscopy and atomic force microscopy. Film thickness, optical band gap (direct and indirect), sheet resistance and figure of merit were computed from spectral transmittance and temperature dependent resistivity data. Lithium doping was found to decrease the value of sheet resistance by an order in magnitude. Activation energy was computed from temperature dependent electrical resistivity data measured in the range 300 to 448 K. The 4 wt.% Li doped SnO2 film was found to have a high value of figure of merit among other films. The results are discussed. [Copyright &y& Elsevier]

Abstract: ‘3d’ transition metal ion doped oxide semiconductors are widely studied for utilization in Spintronics. CuO, a p-type semiconductor with a band gap of 1.2eV was explored for ferromagnetic ordering by doping with Mn. Cu0.95Mn0.05O samples prepared by the standard ceramic and co-precipitation methods were analyzed using X-ray diffraction-Rietveld analysis, differential thermal analysis, scanning electron microscopy and energy dispersive X-ray analysis, respectively. Magnetic measurements using vibrating sample magnetometer on samples prepared by both the methods show possible ferromagnetic behavior at 77K. [Copyright &y& Elsevier]

Abstract: ZnO substituted with transitional metal ions at the cationic site present interesting magnetic properties due to the strong sp–d exchange interaction which are expected to play a vital role in SPINTRONICS applications. The preparation route plays a vital role in the synthesis of single phase oxide diluted magnetic semiconductors (DMS). Zn0.95Ni0.05O prepared by both co-precipitation and ceramic methods were analyzed in detail by powder X-ray diffraction. Pelleted samples examined for their magnetic property using vibrating sample magnetometer indicated ferromagnetic-like behavior at 300K. Comparing the results of measurements performed on both the samples, we conclude co-precipitation method to be more effective in obtaining single phase compound with desirable properties by the relatively low temperature processing of the precipitated hydroxides. [Copyright &y& Elsevier]