Professor of Chemistry, Professor of Materials Science and Engineering
she/her
About
Synthesis and integration of 2-D nanomaterials
Driven by the transition to a sustainable society there is an enormous push to develop nanomaterials with new functionalities. In order to study new nanomaterials systematically and later implement them in novel applications, new synthesis processes and techniques need to be investigated and developed, that are reliable, reproducible and scalable with ultimate control at the nanoscale.
In our group we pioneer atomic layer deposition (ALD) for two-dimensional nanomaterials synthesis. ALD is a scalable, low temperature preparation method for thin films which offers precise thickness control down to the sub-monolayer and can therefore be instrumental for the large area synthesis of 2D materials. The current focus of the group is on ALD of 2D transition metal dichalcogenides (2D-TMDs) for (opto)electronics and catalysis. We use plasma chemistry (plasma-enhanced ALD, PEALD) to control functionalities of the 2D-TMDs, such as morphology [1, 2], materials phase [3] and stoichiometry [4]. Furthermore, by doping, alloying and by the formation of heterostructures we tune the electrical properties of the 2D TMDs, such as the charge carrier concentration and band gap [5].
Our process development goes hand-in-hand with obtaining understanding of the ALD reaction mechanisms at play using for example high-resolution transmission electron microscopy and DFT simulations. In addition, we test the characteristics of the new materials using a range of spectroscopic techniques, electrical measurements and electrocatalysis.
[1] Sharma, A., Verheijen, M. A., Wu, L., Karwal, S., Vandalon, V., Knoops, H. C. M., Sundaram, R., Hoffman, J. P., Kessels W. M. M., Bol, A. A., Low-temperature plasma-enhanced atomic layer deposition of 2-D MoS2 : large area, thickness control and tuneable morphology, Nanoscale (2018), 10, 8615.
[2] Balasubramanyam, S. Bloodgood, M. A., Ommeren, van, M., Faraz, T., Vandalon, V., Kessels, W. M. M., Verheijen, M. A., Bol, A. A., Probing the Origin and Suppression of Vertically Oriented Nanostructures of 2D WS2 Layers, ACS Appl. Mater. Interfaces (2020), 12, 3873-3885
[3] Basuvalingam, S. B., Zhang, Y., Bloodgood, M., Godiksen, R., Curto, A. Hofmann, J. P., Verheijen, M. A., Kessels, W. M. M., Bol, A. A., Low temperature phase-controlled synthesis of titanium di- and tri-sulfide by atomic layer deposition, Chem. Mater. (2019), 31, 9354
[4] Balasubramanyam S., Shirazi, M., Bloodgood, M. A., Wu, L., Verheijen, M. A., Vandalon, V., Kessels, W. M. M., Hofmann, J. P., Bol, A. A., Edge-Site Nanoengineering of WS2 by Low-Temperature Plasma-Enhanced Atomic Layer Deposition for Electrocatalytic Hydrogen Evolution. Chem. Mater. (2019), 31, 5104–5115
[5] Vandalon, V. Verheijen, M. A., Kessels, W. M. M., Bol, A. A., Atomic Layer Deposition of Al doped MoS2: Synthesizing a p-type 2D semiconductor with tunable carrier density, ACS Appl. Nano Mater. (2020), 3, 10200-10208
