Coupled Electron- and Ion-Transfer Processes at a Liquid/Liquid Interface Decorated with Photoactive Nanomaterials.

The influence of the ion transfer on photoinduced electron transfer (ET) reactions was studied on the surface of hyperbranched semiconducting BiVO particles spontaneously adsorbed at the liquid-liquid (L/L) interface between an aqueous LiCl solution and bis(triphenylphosphoranylidene) ammonium tetrakis(pentaflurophenyl)borate (BATB) in 1,2-dichlorethane. The organic electrolyte was supplemented with [Co(bpy)](PF) to accept photoexcited electrons from BiVO under formation of the corresponding Co(II) complex. The L/L interface was stabilized at the orifice of a micropipette (MP) and allowed to record ion transfer cyclic voltammetry (ITCV) by applying a Galvani potential difference between two reference electrodes in the electrolyte solutions with intermittent illumination by visible light (λ>420 nm). The photogenerated holes caused oxidation of water to O. Co(II) and O were detected at constant at an amperometric microelectrode (ME) facing the orifice of the MP in either the organic or the aqueous electrolyte. The overall current exhibits a photocurrent only in the -range, in which the IT of PF is kinetically limited. The amperometric detection of photogenerated products followed the same pattern as the photocurrent in the total current.