Photoconductive ZnO films with embedded quantum dot or ruthenium dye sensitizers

We report a new type of solution-processed photoconductive film based on embedding photosensitizers (semiconductor nanocrystals or ruthenium dye molecules) within conductive ZnO sol-gel matrices. Mixing photosensitizers directly with sol-gel precursors prior to film deposition yields highly colored ZnO films containing well-dispersed sensitizers. These films show internal photoconductivity quantum efficiencies up to similar to 50% and photoresponses over 100 mA/W with visible photoexcitation, competitive with other more complex photodetectors reported recently. This simple motif is attractive for the development of robust sensitized-oxide photodetectors and for fundamental studies of photoinduced charge separation from a variety of molecular or quantum dot sensitizers into conductive oxides. (C) 2013 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.