Prof. Eran Edri

Department of Chemical Engineering, Ben-Gurion University of the Negev, Israel

Metal trichalcogenides and chalcohalides establish a class of soft semiconducting materials with a quasi-one-dimensional crystal structure. These low-symmetry semiconductors have favorable optoelectronic properties for photovoltaic and photoelectrocatalysis: an optical bandgap in the visible-NIR region and a relatively small electron affinity. Moreover, some chalcohalides, such as SbSeI and SbSI, have ferroelectric properties, which can be harnessed to increase the open-circuit voltage in solar energy harvesting devices. However, there are limited synthetic strategies for nanostructured chalcohalides and a limited understanding of their mechanism. In this seminar, I will present two facile routes for transforming Sb2Se3 to SbSeI nanorods, where the Sb2Se3 nanorods acted as templates to form small diameter SbSeI nanorods (diameter < 30 nm). These routes are suitable for a range of other trichalcogenide-chalcohalide transformations. I will also present a detailed experimental and theoretical investigation of the chemical transformation process, how the reaction progresses, and why. Finally, the chalcohalides nanorods show intriguing photoreactivity, surface photovoltaic response, and self-healing properties, which will be discussed as well.