The influence of some coadsorbents and different pH values on the efficiency of DSS cells assembled with phycocyanin was evaluated using quartz crystal microbalance (QCM) and electrochemical techniques as impedance spectroscopy (EIS) and cyclic voltammetry (CV). Chlorophyll, heptadecanoic acid and 7.5 or 8.5 pH values were applied when nanostructured TiO2 electrode was dipped in the dye solution. Best efficiency conversion values were obtained when using fatty acids as coadsorbents, reaching a conversion efficiency of 0.04 % for open cells.