| As one of the most famous and widely used semiconductors, TiO2owns certainoutstanding advantages, such as non-toxic, photochemical stability and low-cost, et al.However, its efficiency of utilizing solar energy is heavily limited due to the widebandgap and the restricted absorbance of visible light. In this thesis, narrow bandgapsemiconductors, mainly are CdSe and Cu2O, were used as sensitizers to couple with TiO2to form heterojunction structures that exhibited highly enhanced photocatalytic efficiency(PE) both under UV and visible light irradiation.We used two-step anodization to grow TiO2nanotube arrays, which was used assubstrate in next experiment. CdSe was successfully deposited on the walls of TiO2nanotube arrays using Electrochemistry Atomic Layer Epitaxy (ECALE). Thickness ofCdSe layer was adjusted by deposition time, deposition potential and PH value. Thehighest electrochemical properties were observed in the sample after7h deposition.Nanocrystalline Cu2O film on titanium dioxide nanotube arrays was synthesized by amultiple-step chemical bath deposition, in which rinsing steps were used to reducedeposition rate and to minimize clogging of the nanotubes. By adjusting the glucoseconcentration in reaction solutions, particles of different sizes were expected to beobtained. Surface morphology, structure, photoelectric properties, and corrosion of thefilm were systematically investigated. It was found that size of cuprous oxidenanoparticles reduced with the increasing of glucose concentration. All the samples afterdeposition possessed enhanced absorption in visible light region while the bestphotocatalytic performance was measured in the sample with very small particles. Impactof deposition amount to performance was discussed. The optimum amount was8cycleswhile the copper content was4%. The sample with10nm particles possessed higherhydrogen yield ability and lower photocorrosion than the sample with35nm particles. |
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