Surface roughened 1-D Au host nanorods for visible light induced photocatalyst

Visible light induced photocatalytic degradation of rhodamine B and hydrogen generation from solar water splitting by hematite (α-Fe ₂O₃) coated gold (Au) nanorods have been investigated, in which two types of α-Fe₂O₃/Au nanorods with different Au surfaces were synthesized and then carefully compared. Vertically aligned smooth Au nanorod and porous Au nanorod arrays were prepared by the electro-deposition method using anodized aluminum oxide templates, followed by deposition of hematite onto nanoporous Au nanorods and smooth Au nanorods to synthesize core/shell like nanostructure. The as-prepared samples were characterized by Field Emission Scanning Electron Microscopy, X-ray Diffraction, and X-ray Photoelectron Spectroscopy. Also, their photocatalytic activities were investigated by photo-degradation of rhodamine B, photocurrent-voltage, and incident photon to current conversion efficiency measurements under AM 1.5G light irradiation. Hematite (α-Fe₂O₃) coated porous Au nanorods showed better photocatalytic activities than α-Fe ₂O₃ coated smooth Au nanorods, showing faster dye degradation rate, higher photocurrent density and better photon harvesting.