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Hybrid nanoarchitectures of AgInS2 and TiO2 photocatalysts were prepared by using a modified sol–gel method. The experimental results reveal that these nanocomposites display enhanced visible light absorption and effective charge carrier separation compared to their pristine parent samples (AgInS2 or TiO2). 0.5 wt % AgInS2 loading was found to be the optimum concentration for photocatalytic applications. More than 95% of doxycycline degradation was achieved within 180 min of solar light illumination. Similarly, the dopant concentrations at lower values (<2 wt %) exhibited 300 times higher H2 generation rate under visible light irradiation compared to AgInS2 and TiO2. The microbial strains (Escherichia coli and Staphylococcus aureus) exhibited a 99.999% reduction within half an hour of simulated solar light illumination. The computational investigation was employed to understand the structural, electronic, and the dielectric properties of AgInS2 and TiO2 composites. The improved photocatalytic results are explained as a result of the decreased rate of exciton recombination. The current investigation opens up new insights into the use of novel ternary heterostructure nanocomposites for improved visible light activity.

Triarylamine-derivatives can self-assemble upon light irradiation in onedimensional nanowires with remarkable hole transport properties.We use a combination of density functional theory and Monte Carlo simulations to predict the nanowires spin-diffusion length. The orbital nature of the nanowires valence band, namely a singlet p-like band localised on N, suggests that hyperfine coupling may be weak and that spin-orbit interaction is the primary source of intrinsic spin relaxation.Thus, we construct a model where the spin-orbit interaction mixes the spins of the valence band with that of three degenerate lower valence bands of sp 2 nature. The model includes also electron-phonon interaction with a single longitudinal mode. We find a room temperature spin-diffusion length of the order of 100 nm, which increases to 300 nm at 200 K. Our results indicate that triarylamine-based nanowires are attractive organic semiconductors for spintronics applications.Functionalized triarylamines are a family of molecules well known in organic electronic applications such as light-emitting diodes, field-effect transistors and more recently multilayered heterojunctions solar cells. 1,2 Triarylamine derivatives dispersed in chloroform solution, when exposed to light, self-assemble in one dimensional (1D) supramolecular nanowire structures. 3 Even more interesting is the fact that the nanowires can be grown across nanogaps so that two-terminal self-assembled devices can be made. Intriguingly such devices display low resistances, with ohmic-like current-voltage, I-V, characteristics. This points to the nanowires being good charge conductors, 4 i.e. being potentially useful for electronic applications.In this communication we report on a first principle calculation of the spin-diffusion length of one of such nanowires, i.e. we provide an assessment on whether or not triarylamines derivatives can be used as materials platform for organic spintronics. 5 In particular, we focus on nanowires forming from the precursor depicted in Fig. 1(a), for which hole transport experimental data are available, 4 and for which we have recently estimated 6 room temperature hole mobility of the order of 10 cm 2 V À1 s À1 , for a pristine defect free nanowire structure.The electronic structure of the molecule in the gas phase is calculated by using density functional theory (DFT), at the level of the hybrid B3LYP functional, 7 for the molecule's geometry optimized by conjugate gradient (to forces smaller than 2 Â 10 À5 Hartree per Bohr). In particular we use the DFT numerical implementation of the Gaussian09 suit 8 and the 6-31G* basis set. We obtain a gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of 4.1 eV. Most importantly for the discussion here the HOMO is an orbital singlet strongly localized on the central N atom of the triarylamine unit. An orbital decomposition reveals its strong p z character, as demonstrated by the charge density isosurface of Fig. 1(b). Note that the orbital character...