Surface Engineering of Two-Dimensional Hydrogenated Silicon Nanosheets for Tailored Applications

Abstract

Approaching the predicted limits by Moor’s law, which come with the shrinking size of electronics, science needs to find alternatives for the fabrication of novel devices. Within the last decades, more and more hybrid materials have been developed based on 0D- 1D- and also 2D nanomaterials. This development is also driven by the search for fast, cheap, reproducible and environmental-friendly low-cost devices. Hydrogenated silicon nanosheets (SiNSs) consist of just a buckled monolayer of sp3-hybridized silicon atoms, which are decorated with hydrogen atoms. The sheets show green and consistent photoluminescence at ~510 nm and are predicted show semiconducting behaviour. SiNSs may be used as an alternative for not only bulk silicon, but also already known two dimensional materials. Well-studied and established nanosilicon surface chemistry offers solid ground for precise surface engineering, leading to control of the nanomaterial for reproducible device fabrication. New applications and processing techniques can thus be developed, which lead to facile fabrication of enhanced sensors and (opto)electronics. In this regard, research pursues additionally the combination of organic materials’ properties with those of the nanomaterials, building the basis for new devices. One example is the combination of the widely used organic semiconductor poly(3-hexylthiophene-2,5-diyl) with the precisely modified SiNSs. Again, surface engineering plays the key role in the hybrid materials’ synthesis and subsequent application. This gives the opportunity to tune the properties of the hybrid material in the desired way. In this context, we present different ways of surface engineering with the modification of SiNSs as an example for the subsequent application in various (opto)electronic devices (e.g., SGFETs and photonic sensors).