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In this work, we have fabricated hybrid heterojunction solar cells with structure ITO/ZnO/P3HT:PCBM:CTSe NCs (optimized weight percentage 10 wt%)/MoO3/Ag (device SM10). A thin layer of molybdenum oxide MoO3 prepared by peroxomolybdic acid organosol as the precursor was used as hole transport layers (HTLs). The performance of the device was compared with ITO/ZnO/P3HT:PCBM:CTSe NCs/Ag(device S10). The important parameters such as global charge carrier mobility (µ), effective charge carriers lifetime (τn) and charge diffusion time (τd) have been extracted from electrochemical impedance spectroscopy (EIS) performed at the bias of 0.1 V in the dark. The Nyquist plot obtained from EIS has demonstrated effective carriers lifetime, global mobility and charge diffusion time for a device SM10 as 6.46 ms, 12.6 × 10−4 cm2 V−1 S−1 and 5.2 µs and for device S10 as 5.65 ms, 9.58 × 10−4 cm2 V−1 S−1 and 6.8 µs, respectively. [ABSTRACT FROM AUTHOR]

The present work reports on the relatively higher saturation magnetization values of Fe/Fe3O4 nanocomposites. For example, the nanocomposites of Fe obtained after milling for 10 h with 5, 10 and 15 wt% of Fe3O4 had displayed saturation magnetization values of 210, 238 and 216 Am2 kg–1, respectively, in contrast to 218 Am2 kg–1 of bulk Fe. Similarly, the maximum magnetization values for the nanocomposites after 20 and 30 h of milling were 215 and 190 Am2 kg–1 for the sample containing 5 and 15 wt% of Fe3O4, respectively. The values of HC and Mr suggest that nanocomposites exhibit soft ferromagnetic behaviour. The ball milling also reduced the crystallite and particle size of Fe from microndimension to nanometres. This was confirmed from X-ray diffraction, transmission electron microscopy and scanning electron microscopy analyses. The crystallite size of pure Fe decreased to 35, 20 and 19 nm, respectively, for the samples having 5, 10 and 15 wt% of Fe3O4 after 10 h of milling. The crystallite size decreased further with increased milling time. [ABSTRACT FROM AUTHOR]

SmxBi3–xTiNbO9 (SBTN) with x = 0 , 0.2, 0.4, 0.6, 0.8 and 1.0, a novel type of ceramic was prepared by a conventional solid-state reaction method. X-ray diffraction patterns confirm the formation of a single-phase, and lattice parameters were calculated based on the parent compound Bi3TiNbO9 (BTN). Well-defined grains were seen in the scanning electron microscopy pictures. A kink observed near 400°C for all the samples in the dielectric plot as well as in the stretched exponential parameter (β) vs. temperature plot reveals the dielectric relaxation of the samples. The tolerance factor (t) was found to increase with increase in the size of the A-site (Bi-site) modified ion (Sm). Impedance and modulus spectroscopic studies were conducted to understand the plausible reason for the dielectric relaxation. The relaxation was found to be well-fit with Arrhenius equation. SBTN samples showed lower dielectric loss compared to BTN. The remnant polarization, obtained from experimental, was found to be less than that of theoretically calculated polarization, using Shimakawa's formula. The proposed defect mechanism was interpreted using FTIR and Raman spectroscopic studies. [ABSTRACT FROM AUTHOR]