Formation of small particles of lead iodide, mercuric iodide, and bismuth iodide layered semiconductors

Defect Engineering of Earth-Abundant Solar Absorbers BiSI and BiSeI

Bismuth-based solar absorbers have recently garnered attention due to their promise as cheap, nontoxic, and efficient photovoltaics. To date, however, most show poor efficiencies far below those seen in commercial technologies. In this work, we investigate two such promising materials, BiSI and BiSeI, using relativistic first-principles methods with the aim of identifying their suitability for photovoltaic applications. Both compounds show excellent optoelectronic properties with ideal band gaps and strong optical absorption, leading to high predicted device performance. Using defect analysis, we reveal the electronic and structural effects that can lead to the presence of deep trap states, which may help explain the prior poor performance of these materials. Crucially, detailed mapping of the range of experimentally accessible synthesis conditions allows us to provide strategies to avoid the formation of killer defects in the future.

Surface-functionalized monolayered nanodots of a transition metal oxide and their properties

Transition metal oxide monolayers with controlled lateral size, surface chemistry, and properties are obtained in a nonpolar organic medium.

Hydrophobic monolayered nanoflakes of tungsten oxide: coupled exfoliation and fracture in a nonpolar organic medium

Coupled exfoliation and fracture induced formation of hydrophobic monolayered nanoflakes of tungsten oxide in a nonpolar organic medium.