The formation of an accumulation layer on a nanocrystalline TiO2 (anatase) electrode was studied by cyclic voltammetry in solutions of MCF(3)SO(3) (M = Li, Na, K, Cs, NBu(4); Bu = n-butyl) + propylene carbonate. In the LiCF3SO3 solution, the electron accumulation is accompanied by a reversible insertion of Li+ into the anatase lattice. Other cations give only capacitive effects at comparable conditions. The stability of electrolyte solutions against cathodic breakdown was studied by in-situ subtractively normalized interfacial Fourier transform IR (SNIFTIR) spectroscopy. The reduction of trace water triggers solvent decomposition. Prolonged application of voltammetric scans shifts the flatband potential negatively and decreases the integral voltammetric charge. The formation of the accumulation layer follows complex kinetics, which are attributed to electron trapping in surface states and charge propagation in the nanocrystalline semiconducting skeleton.