Quantum dynamics of light-induced charge injection in a model dye-nanoparticle complex

CHRISTIAN F.A. NEGRE; VALERIA C. FUERTES; M. BELÉN OVIEDO; FABIANA Y. OLIVA; CRISTIÁN G. SÁNCHEZ

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Lugar: Washington; Año: 2012 vol. 116 p. 14748 - 14748

1932-7447

e present a detailed description of the direct charge injectionmechanism in a coupled dye−TiO2 nanoparticle (NP) using a full quantumdynamical simulation framework. The method employed here is based on a timedependenttight-binding model to describe the system under nonequilibriumconditions. By using this tool, we performed a simulation showing a full timedependentpicture of the photoabsorption process in type-II dye-sensitized solar cells(direct charge injection mechanism from the dye to the TiO2 NP). This task isaccomplished by tuning the frequency of an applied sinusoidal time-dependentelectric field with the frequency of the dye−TiO2 NP?s main absorption peak. We findthat during the field irradiation there is a net charge transfer from the dye to the NPsuperposed with a typical charge oscillation due to absorption of radiant energy.