Characterization of ZnO as substrate for DSSC

Abstract

We present a complete analysis of the photoinjection process in 3 nm spherical ZnO nanoparticles with different dyes attached to their surface. The study was carried using a TD-DFTB model to describe the quantum dynamics of charge transfer in the presence of an external time dependent electric field simulating resonant illumination. The ZnO + dye systems have been classified according to the injection process (type I and type II) that they present. In addition, the calculated charge transfer shows that many dyes present hole injection into the nanoparticle. We have classified the charge transfer into holes or electron and compare these results with the TiO2 + dye system obtained from the literature.

Photoinduced charge-transfer in chromophore-labeled gold nanoclusters: quantum evidence of the critical role of ligands and vibronic couplings

“…21 The latter can be used to access not only the absorption spectrum but the electron dynamics following excitation. 22 This method was succesfully used in the last decade to study the optoelectronic properties of a wide variety of organic and inorganic materials: the absorption spectra and photophysical properties of photosyntetic pigments 23,24 and DNA-protected silver emitters 25,26 , plasmonic properties of gold, 27-29 silver 28,29 and aluminium 30 metallic nanoparticles, optical properties of carbon-based materials like graphene nanoflakes 31 and graphene nanoribbons 32 and photoinduced charge transfer mechanisms elucidation in metal oxides [33][34][35][36][37] for dye-sensitized solar cells (DSSC) and molecular aggregates 38,39 for organic solar cells (OSC). These studies were performed within the electron-only quantum dynamics approach without considering nuclei movement, yet reaching a good agreement with experiments.…”

Surface Functionalization of Metal Oxide Semiconductors with Catechol Ligands for Enhancing Their Photoactivity

“…Reproduced with permission. [ 120 ] Copyright 2018, Royal Society of Chemistry. F) Schematic illustration of PDA‐sensitized solar cells proposing the photogenerated CT mechanism.…”

“…Considering rising demand for clean energy in recent years, researchers introduced the third generation of solar cells, DSSCs, that are a type of photovoltaic devices. [ 48,120,121 ] A photovoltaic cell can directly convert solar energy. In general, DSSC photovoltaic cells are composed of the following elements: a WE constructed from a porous dye‐sensitized photoactive semiconductor layer deposited onto a transparent anode, an electrolyte layer, and a CE cathode (Figure 4B).…”

“…Fabrication cost and sunlight to electricity conversion efficiency are main challenges in the solar cells research area. [ 120 ] TiO 2 , ZnO, and SnO 2 metal oxides are commonly used as photoanodes in DSSCs. [ 120 ] Excellent electrochemical properties, strong bonding ability to form CT complexes with metal oxides, and photovoltaic performance of dyes containing catechol make them promising candidates.…”

“…[ 120 ] TiO 2 , ZnO, and SnO 2 metal oxides are commonly used as photoanodes in DSSCs. [ 120 ] Excellent electrochemical properties, strong bonding ability to form CT complexes with metal oxides, and photovoltaic performance of dyes containing catechol make them promising candidates. [ 46 ] Upon photoexcitation, an electron of catechol dye HOMO transfers to metal oxide CB by direct one‐step process (type II).…”