Fig. 1. Schematic of TiN/Al₂O₃ film preparation

Fig. 2. Schematic of CdSe/TiN/Al₂O₃ heterojunctions preparation

Fig. 3. Electrochemical characterization of TiN/Al₂O₃ film electrodes. (a) Curves of the surface potential with deposition time on TiN/Al₂O₃ film electrodes; (b) volt-ampere curves of TiN/Al₂O₃ film electrodes

Fig. 4. Absorption spectra of TiN film and CdSe/TiN film at 50 μA depositing time

Fig. 5. Fluorescence spectra characterization of the samples. (a) Fluorescence spectra of the porous Al₂O₃ film and CdSe quantum dot solution; (b) fluorescence spectra of CdSe/TiN/Al₂O₃ heterojunctions at different depositing currents

Fig. 6. Diagram of optical generating carriers transfer CdSe/TiN/Al₂O₃ heterojunction

Fig. 7. AFM morphology of TiN/Al₂O₃ film and CdSe/TiN/Al₂O₃ heterojunction. (a) AFM morphology of TiN/Al₂O₃ film; (b) AFM morphology of CdSe/TiN/Al₂O₃ heterojunction

Fig. 8. Optical spectral morphology of CdSe/TiN/Al₂O₃ heterojunction. (a)(b) Distribution of fluorescence peaks and its intensity from TiN/Al₂O₃ interface; (c)(d) distribution of fluorescence peaks and its intensity from CdSe/TiN interface