Ordered CdSe-sensitized TiO2 inverse opal film as multifunctional surface-enhanced Raman scattering substrate

The surface-enhanced Raman scattering (SERS) study on semiconductor material has attracted much attention, but the traditional semiconductor materials possess low SERS sensitivity and single function, which cannot meet the need of people very well. Here, the ordered three-dimensional CdSe-sensitized TiO2 (CdSe-TiO2) composite film with inverse opal structure (IOS) and multifunction was synthesized successfully. The as-prepared CdSe-TiO2 IOS film was first used as the excellent SERS substrate and photoelectrochemical material. The synergistic effect of slow photons, multiple scattering and CdSe sensitization make the SERS substrate more sensitive. The detection limit of the methylene blue (MB) on CdSe-TiO2 IOS film can be as low as 7 × 10−9 M. In addition, CdSe-TiO2 IOS exhibits excellent photoelectric converting performance, the photocurrent density of CdSe-TiO2 IOS can achieve 0.924 mA/cm2 under chopped light illumination at a fixed bias of 0 V versus Ag/AgCl. The above performance enhancement of CdSe-TiO2 IOS film makes it becoming a promising multifunctional material to be used in SERS detection and photoelectrochemical field.