Meng, ShengKaxiras, Efthimios2017-07-112010Meng, Sheng, and Efthimios Kaxiras. 2010. “Electron and Hole Dynamics in Dye-Sensitized Solar Cells: Influencing Factors and Systematic Trends.” Nano Letters 10 (4) (April 14): 1238–1247. doi:10.1021/nl100442e.1530-69841530-6992http://nrs.harvard.edu/urn-3:HUL.InstRepos:33371484We investigate electron and hole dynamics upon photon excitation in dye-sensitized solar cells, using a recently developed method based on real-time evolution of electronic states through time-dependent density functional theory. The systems we considered consist of organic sensitizers and nanocrystalline \(TiO_2\) semiconductors. We examine the influence of various factors on the dynamics of electrons and holes, including point defects (vacancies) on the \(TiO_2\) surface, variations in the dye molecular size and binding geometry, and thermal fluctuations which result in different alignments of the electronic energy levels. Two clear trends emerge: (a) dissociated adsorption of the dye molecules leads to faster electron injection dynamics by reducing interfacial dipole moments; (b) oxygen vacancy defects stabilize dye adsorption and facilitate charge injection, at the cost of lower open circuit voltage and higher electron−hole recombination rate. Understanding of these effects at the atomic level suggests tunable parameters through which the electronic characteristics of dye-sensitized solar cell devices can be improved and their efficiency can be maximized.en-USUltrafast dynamicscharge injectionTDDFTsolar cellenergy harvestJournal Article10.1021/nl100442e