Somil Gupta MSc
Ornstein Laboratory, room 1.73
Princetonplein 1, 3584 CC Utrecht
P.O. Box 80 000, 3508 TA Utrecht
phone: +31(0)30 253 3125
secretariat: +31(0)30 253 2952
Supervisor: Dr.ir. M.A. van Huis
Promotor: Prof.dr.ir. M. Dijkstra
Employed 15 July 2014 – 14 July 2018
Funded by FOM
Density functional theory (DFT), Ab initio Molecular Dynamics (AIMD), Water Splitting
Efficient hydrogen production using renewable solar energy has emerged as an exciting frontier in alternate energy research. Recently, new nano-heterostructures using narrow-bandgap semiconductors, capped with metal catalysts, (CdSe – CdS – Pt/Au nanostructures) have been shown to be extremely efficient for photo-catalytic water-splitting, and hence, for clean H2 production.[1,2] Experimental studies cannot accurately access the underlying molecular mechanisms, and factors which guide this catalytic process; hence, simulation techniques using the first-principles studies like DFT, supported with MD for relevant temperatures can play a pivotal role in understanding and developing even more efficient photo-catalytic processes.
Experiments have revealed that the photoexcited electrons from the semiconductor accumulate at the metal caps, which act as the catalytic site for water-splitting.(Figure 1). However the questions which are of great interest are: how is the wetting layer of water at these structures, and what are the other factors affecting the catalytic mechanism. Our goal is to develop and exploit upon first-principle approaches, to understand the adsorption, dissociation of water molecules and liquid-water at the CdS surfaces, and of the derived heterostructures. We further aim to extend our understanding at relevant temperatures using ab initio molecular dynamics (AIMD) studies.
Figure 1: Schematic of the photo-catalytic splitting of water using semiconductor nano-heterostructures
 L. Amirav et al., Jour. of Phys. Chem. Letters, 1, 1051 (2010)
 N. Bao et al., Chem. Mater., 20, 110–117 (2008)