Silicon nanowires arrays for visible light driven photocatalytic degradation of rose bengal dye

The uniform growth of aligned silicon nanowires (SiNWs) on p-type silicon (Si) wafer were obtained by metal-assisted chemical etching (MCE) technique. MCE was performed using aqueous solution of AgNO₃ and HF for Ag deposition and etching respectively. The morphological characterizations showed well-aligned and uniform growth of SiNWs with the average diameter of ~80–100 nm. The grown SiNWs were applied as effective photocatalyst for the photocatalytic degradation of rose bengal (RB) dye under the light illumination. The high degradation rate of ~96 % within ~90 min over the surface of SiNWs was observed for the degradation of RB dye. The enhanced photocatalytic activity might due to the increase of electron trapping and reduction in the recombination rate.