In this paper, we synthesized Y, N co-doped TiO2 nanoparticles via a simple sole-gel method. The incorporated yttrium and nitrogen increased the BET surface area and porosity of the nanoparticles, as the sample 100-300-0.5 reached 105.9 m(2)/g, which largely improved the dye adsorption ability and obviously enhanced the J(sc). By optimizing doping amount of TiO2, sample 100-300-0.5, for which the doping concentration characterized by XPS survey was 0.30% and 0.48% of yttrium and nitrogen, respectively, showed the best efficiency of 5.41% without any post-treatments on the electrode, 18% higher than the un-doped sample100-0-0. According to EIS measurements, charge transfer resistance could decrease to as low as 39.3 Omega in the co-doped samples, which was almost half of the un-doped TiO2. This work may open up more studies to apply co-doped TiO2 in photovoltaic cells. (C) 2015 Elsevier B.V. All rights reserved.