Advances in Condensed Matter Physics / 2015 / Article / Fig 25

Research Article

Electrochemical Characterization of Nanoporous Nickel Oxide Thin Films Spray-Deposited onto Indium-Doped Tin Oxide for Solar Conversion Scopes

Figure 25

Hypothesis of mechanism of electrochemically induced charge injection from photoexcited ERY sensitizer to mesoporous RDS/CS NiOx within the potential range of NiOx oxidation (2.8–3.7 V versus Li+/Li). (a) Electron is injected in the valence band (VB) of oxidized RDS/CS NiOx from excited ERY colorant; (b) upon neutralization of the hole that has been electrochemically injected in NiOx the colorant ERY would retain a positive charge with formation of the combination ERY+-NiOx. (c) NiOx can regenerate the hole by back donation of an electron from the VB of neutral NiOx to the HOMO of ERY+. Further electrochemical oxidation of NiOx can occur also when the dye sensitizer is in the oxidized state (not shown).