The atomic layer deposition (ALD) technique is applied to coat Ag nanowires (NWs) with a highly uniform and conformal TiO layer to improve the stability and sustainability of Ag NW transparent conductive films (TCFs) at high temperatures. The TiO layer can be directly deposited on Ag NWs with a surface polyvinylpyrrolidone (PVP) coat that acts a bed for TiO seeding in the ALD process. The ALD TiO layer significantly enhances the thermal stability at least 100 fold when aged between 200-400 °C and also provides an extra function of violet-blue light filtration for Ag NW TCFs. Investigation into the interaction between TiO and Ag reveals that the conformal TiO shell could effectively prevent Ag from 1D-to-3D ripening. However, Ag could penetrate the conformal TiO shell and form nanocrystals on the TiO shell surface when it is aged at 400 °C. According to experimental data and thermodynamic evaluation, the Ag penetration leads to an interlayer composed of mixed Ag-AgO-amorphous carbon phases and TiO at the Ag-TiO interface, which is thought to be caused by extremely high vapor pressure of Ag at the Ag-TiO interface at a higher temperature (e.g., 400 °C).

Multicore/shell PbCdS quantum dots (QDs) with an extraordinarily large Stokes shift of more than 550 nm are reported in this study. The QDs were prepared from a Pb–Cd cation-exchange method at an elevated reaction temperature for an extended reaction time, resulting in PbS–CdS domain separation within the core/shell PbS/CdS QD matrix. As a result, the QDs with the multidomain structure possess the first exciton absorption and photoluminescence wavelengths of 450 and 1002 nm, respectively, leading to an unusually large Stokes shift. The unique QDs are considered promising in some applications such as a down-shifting layer for solar harvesting.

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