Synthesis and Characterization of 2D Materials


Synthesis and Characterization of 2D Materials

Growth mechanism studies
The formation of 2D materials at the single- and few-layer level is very challenging and requires basic knowledge of the processes taking place during growth. Moreover, their controlled formation on large-scales is a prerequisite for the successful integration of 2D materials in new and existing technologies. In order to address this important issue, we use chemical vapor deposition (CVD) methodologies for the growth of transition metal dichalcogenides (TMDs), mainly of the Mo and W families (MoX2 and WX2; X = S, Se and Te). Some basic questions we are trying to address: what's the influence of the surface on the growth? What's the influence of the precursor type (solid, liquid and gas – volatile or not, etc.)? What are the requirements to grow a single-layer over large-areas (surface-mediated growth, layer-by-layer, 3D islands growth, etc.)? Furthermore, we are targeting the growth of more exotic layered materials not explored so far.


In-Situ and Ex-Situ Doping and Alloying of 2D Materials
The chemical composition of materials in general greatly affect their electronic and optical properties. Here we aim to control the chemical composition of layered materials during or after their growth. The doping and alloying is characterized by various techniques: Raman spectroscopy and mapping, Photoluminescence spectroscopy, XPS, EDS, TOF-SIMS, etc.


Controlled Formation of Vertical and Horizontal Heterostructures
Heterostructures made of single- or few- atom-thick materials have attracted a wide interest in the scientific community due to their potential in nanoelectronics and optoelectronics. Here we employ the lessons learned from the previous tasks in order to create novel vertical and horizontal heterostructures. This is followed by a fully structural, chemical, electrical and optoelectrical characterization.


What is the influence of Mechanical Strains, Temperature and Chemical Environment on the Intrinsic Properties?   
Commercial and home-made cells are used in order to answer the above question on the synthesize materials. These questions are crucial for the integration of such materials into different technologies as well as for the development of new devices (such as sensors, electrical switches, etc.).


When 2D meets 3D: The formation of Novel 3D Structures
Here we aim to create novel 3D functional materials made of 2D layered materials for a wide range of applications, such as ultra-light and strong materials, thermal management, composite materials, catalysis, as electrodes in supercapacitors and batteries, etc.