“…A lot of work on the dye sensitization of TiO 2 , − ZnO, − and SnO 2 , − with various dyes, for example, rhodamine, rose bengal, methylene blue, cresyl violet, ruthenium complexes, etc., has been reported in the past from various labs around the world. In these studies, the semiconductors employed had been largely in the single or polycrystalline form.…”