Influence of Seeding and Bath Conditions in Hydrothermal Growth of Very Thin (~20 nm) Single-Crystalline Rutile TiO2 Nanorod Films

摘要

New seeding conditions have been examined for the hydrothermal growth of single-crystalline rutile TiO2 nanorods. Rutile nanorods of ~20 nm diameter are grown from seed layers consisting of either (A) TiO2 or MnOOH nanocrystals deposited from suspension, or (B) a continuous sheet of TiO2. These seed layers are more effective for seeding the growth of rutile nanorods compared to the use of bare F-SnO2 substrates. The TiO2 sheet seeding allows lower concentration of titanium alkoxide precursor relative to previously reported procedures, but fusion of the resulting TiO2 nanorods into bundles occurs at higher precursor concentration and/or longer growth duration. Performance of polymer-oxide solar cells prepared using these nanorods shows a dependence on the extent of bundling as well as rod height.