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CdSe has attracted interest as the absorber layer in photoelectrochemical cell applications. In this work, titania nanotubes thin film electrodes were prepared by the anodisation method of titanium foil were used due to their ability to produce a uniformly stable structure with high surface area, excellent charge transfer, low interfacial grain boundaries and effective absorption of light. Three electrochemical deposition techniques were used to deposit CdSe onto TiO2 NTAs, namely potentiostatic deposition, cyclic voltammetric deposition, and pulse electrodeposition techniques as a novel to compare between these methods. X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM) coupled with energy dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HRTEM), and UV–Visible diffuse reflectance spectroscopy were used for the characterization of CdSe/TiO2 NTAs nanostructures. The photoelectrochemical performance of the nanostructured CdSe/TiO2 NTAs was investigated in 0.01 M Na2S under visible light illumination. The use of pulse electrodeposition resulted in a greater uniformity in the distribution of CdSe loaded onto TiO2 nanotube arrays. Thus the performance of semiconductor heterostructures prepared by this technique shows a substantial improvement compared to the other two techniques.

CdSe has attracted interest as the absorber layer in photoelectrochemical cell applications. In this work, titania nanotubes thin film electrodes were prepared by the anodisation method of titanium foil were used due to their ability to produce a uniformly stable structure with high surface area, excellent charge transfer, low interfacial grain boundaries and effective absorption of light. Three electrochemical deposition techniques were used to deposit CdSe onto TiO2 NTAs, namely potentiostatic deposition, cyclic voltammetric deposition, and pulse electrodeposition techniques as a novel to compare between these methods. X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM) coupled with energy dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HRTEM), and UV–Visible diffuse reflectance spectroscopy were used for the characterization of CdSe/TiO2 NTAs nanostructures. The photoelectrochemical performance of the nanostructured CdSe/TiO2 NTAs was investigated in 0.01 M Na2S under visible light illumination. The use of pulse electrodeposition resulted in a greater uniformity in the distribution of CdSe loaded onto TiO2 nanotube arrays. Thus the performance of semiconductor heterostructures prepared by this technique shows a substantial improvement compared to the other two techniques.

Solar energy is an alternative sustainable energy resource that can be harvested using photoelectrochemical cell comprised of inorganic sensitized nanostructured oxide semiconductor electrode. In this work, pulse electrodeposition was used to deposit CdSe onto titanium dioxide nanotube arrays (TiO2 NTAs). TiO2 NTAs are commonly used in the nanostructured photoelectrochemical cells due to their high surface area, fewer interfacial grain boundaries and excellent charge transfer between interfaces. Duty cycle of pulse electrodeposition played an important role in the formation of CdSe nanoparticles. A significant enhancement in the photoelectrochemical performance was observed for the heterostructure of CdSe/TiO2 NTAs. CdSe/TiO2 NTAs prepared at 50% duty cycle exhibited maximum photocurrent of 1.94 mA cm−2 and photoconversion efficiency of 1.18% which was 59 times higher than bare TiO2 NTAs. These results demonstrated that significant enhancement in the photoconversion efficiency could be obtained by incorporating CdSe as sensitizer into the TiO2 nanotube arrays via pulse electrodeposition technique.

Solar energy is an alternative sustainable energy resource that can be harvested using photoelectrochemical cell comprised of inorganic sensitized nanostructured oxide semiconductor electrode. In this work, pulse electrodeposition was used to deposit CdSe onto titanium dioxide nanotube arrays (TiO2 NTAs). TiO2 NTAs are commonly used in the nanostructured photoelectrochemical cells due to their high surface area, fewer interfacial grain boundaries and excellent charge transfer between interfaces. Duty cycle of pulse electrodeposition played an important role in the formation of CdSe nanoparticles. A significant enhancement in the photoelectrochemical performance was observed for the heterostructure of CdSe/TiO2 NTAs. CdSe/TiO2 NTAs prepared at 50% duty cycle exhibited maximum photocurrent of 1.94 mA cm−2 and photoconversion efficiency of 1.18% which was 59 times higher than bare TiO2 NTAs. These results demonstrated that significant enhancement in the photoconversion efficiency could be obtained by incorporating CdSe as sensitizer into the TiO2 nanotube arrays via pulse electrodeposition technique.

Low temperature hydrothermal method was used to produce a large surface area ZnO NRs on conductive glass. The same method was used to fabricate a photoelectrode of Ag2S quantum dots onto the nanorod arrays. Ag2S QDs/ZnO NRAs heterostructure was employed as photoanode in a standard 3-electrodes photoelectrochemical cell. A significant enhancement in the photoelectrochemical performance was observed for the Ag2S QDs/ZnO upon heat treatment 400 °C which displayed an impressive photoconversion efficiency of 4.08% by achieving ∼10-times higher compared to bare ZnO NRAs. This enhancement was attributed to the improved morphological structure, crystallinity and optical properties of the synthesised heterostructures.

Low temperature hydrothermal method was used to produce a large surface area ZnO NRs on conductive glass. The same method was used to fabricate a photoelectrode of Ag2S quantum dots onto the nanorod arrays. Ag2S QDs/ZnO NRAs heterostructure was employed as photoanode in a standard 3-electrodes photoelectrochemical cell. A significant enhancement in the photoelectrochemical performance was observed for the Ag2S QDs/ZnO upon heat treatment 400 °C which displayed an impressive photoconversion efficiency of 4.08% by achieving ∼10-times higher compared to bare ZnO NRAs. This enhancement was attributed to the improved morphological structure, crystallinity and optical properties of the synthesised heterostructures.

High density and vertically aligned zinc oxide nanorod arrays (ZnO NRs) have been prepared directly on indium-doped tin oxide (ITO) substrates via two-steps preparation: sol-gel spin coating and hydrothermal process. The nanostructured ZnO was characterized for its morphology, crystalline structure and optical properties by using field emission scanning electron microscopy (FESEM), X-ray diffractometry, and ultraviolet-visible spectroscopy respectively. In addition, the photoeletrochemical (PEC) properties were investigated through photocurrent measurements. The ZnO NRs/ITO had wurtzite-structured (hexagonal) ZnO and preferred growth along (0001) direction. When the growth time was 4 h, ZnO NRs/ITO showed impressive photoresponse. The PEC analysis verified that the ZnO NRs gave better photocurrent response and photoconversion efficiency with approximately 42 times greater than seed layer.

High density and vertically aligned zinc oxide nanorod arrays (ZnO NRs) have been prepared directly on indium-doped tin oxide (ITO) substrates via two-steps preparation: sol-gel spin coating and hydrothermal process. The nanostructured ZnO was characterized for its morphology, crystalline structure and optical properties by using field emission scanning electron microscopy (FESEM), X-ray diffractometry, and ultraviolet-visible spectroscopy respectively. In addition, the photoeletrochemical (PEC) properties were investigated through photocurrent measurements. The ZnO NRs/ITO had wurtzite-structured (hexagonal) ZnO and preferred growth along (0001) direction. When the growth time was 4 h, ZnO NRs/ITO showed impressive photoresponse. The PEC analysis verified that the ZnO NRs gave better photocurrent response and photoconversion efficiency with approximately 42 times greater than seed layer.