Shear Exfoliation and Photoresponse of 2D-Layered Gallium Selenide Nanosheets

Layered two-dimensional materials have attracted much attention because of their interesting physical properties for nanoelectronic and optoelectronic applications. In this work, Gallium Selenide (GaSe) nanosheets are exfoliated by the shear exfoliation method to produce dispersion of various GaSe nanosheets. The morphological features are examined using Raman Spectroscopy and Atomic Force Microscopy and the optical band gap was estimated to be 2.1 eV using Tauc's Plot. The heterojunction comprising GaSe nanosheets and n-type silicon was fabricated which exhibits rectifying behavior and also prominent photoresponse was observed. The obtained results suggest the potential of shear exfoliated GaSe nanosheets for photodetection and next-generation optoelectronics.