The long-forgotten silicon telluride—a silicon-based semiconductor compound—is seeing a revival of interest. Researchers at Brown University, USA, believe it to be a promising 2-D material that could improve the performance of batteries and LEDs. They have already come up with new ways to grow silicon telluride and control its growth so as to form microscopic structures like nanoribbons, flat nanoplates, or standing nanoplates that could benefit many commercial applications.
The findings of Kristie Koski, a chemistry professor at the university, and her team have been published in the journal Nanoletters.
“Silicon-based compounds are the backbone of modern electronics processing,” Koski was quoted as saying by The Brown Daily Herald — a news bulletin for the Brown University. “Silicon telluride is in that family of compounds, and we’ve shown a totally new method for using it to make layered, two-dimensional nanomaterials.”
The researchers chose silicon telluride because it is silicon based, forms graphene like layers and is a chalcogenide like molybdenum disulfide—the current favourite among 2-D materials.
“What makes silicon telluride very attractive as a 2-D material is that it can be exfoliated or reduced to a monolayer material just like graphene,” Koski explained in an email interview with IEEE Spectrum. “It is completely transparent but brilliant red. Also, it is a native p-type semiconductor. In the world of 2-D materials, very few are natively p-type, with phosphorene (2-D phosphorus) being one of the few examples that comes to mind,” she added.
Silicon telluride exhibits a photoluminescence peak in the red, which makes it a potential candidate for use in LEDs or as a photodetector. The layered structure of materials synthesised using silicon telluride can also take up lithium and magnesium, which means silicon telluride could also be used to make electrodes in these batteries—Koski pointed out.
The researchers were able to create different structures by tweaking the fabrication process. As each of the shapes created has a different orientation of the material’s crystalline structure, all the shapes exhibit different properties and could find different applications.
Encouraged by these findings, Koski and her team plan to further test the material’s electronic and optical properties.
Written by Uma Gupta, contributing author for Technology.Org