Fabrication of TiO2/CuSCN Bulk Heterojunctions by Profile-Controlled Electrodeposition

We demonstrate a facile bottom-up growth of CuSCN - a widely used hole conducting material, in mesoscopic TiO2 films by electrodeposition in the presence of TiO2 compact layer. The profile-controlled growth of CuSCN in the nanopores of mesoscopic TiO2 is realized by judiciously optimizing the electrolyte concentration and applied potential, so that the effective electron diffusion length in TiO2 is much shorter than film thickness and the electrodeposition is strictly confined within very narrow region from the conducting substrate. The TiO2/CuSCN heterojunctions exhibit a pore filling ratio of similar to 80% and show good rectifying properties, which is anticipated to be an important step forward to the facile fabrication of bulk heterojunction for nanostructured solar cells or 3D batteries. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.028206jes] All rights reserved.