Innovation in the field of semiconductor materials and devices have to a large extent underpinned the dramatic developments which have unfolded in the area of information and communication technologies over the past 50 years. The ability to form logic devices, memory elements, light emitting diodes, and lasers directly into semiconducting materials has had a transformative effect on modern society. Looking beyond the era of conventional scaling, the drive towards the internet of things, will require the integration of sensors and optical devices with conventional logic and memory elements. The aim of this article is to give a brief overview of the large-area growth of some 2D transition metal dichalcogenide layered materials by MBE and CVD methods, followed by examples of how these 2D materials can be employed in electron devices and optoelectronic structures and devices.