Highly ordered TiO_2 nanotube arrays(NTAs) on Si substrate possess broad applications due to its high surfaceto-volume ratio and novel functionalities, however, there are still some challenges on facile synthesis. Her...Highly ordered TiO_2 nanotube arrays(NTAs) on Si substrate possess broad applications due to its high surfaceto-volume ratio and novel functionalities, however, there are still some challenges on facile synthesis. Here, we report a simple and cost-effective high-field(90–180V) anodization method to grow highly ordered TiO_2 NTAs on Si substrate,and investigate the effect of anodization time, voltage, and fluoride content on the formation of TiO_2 NTAs. The current density–time curves, recorded during anodization processes, can be used to determine the optimum anodization time. It is found that the growth rate of TiO_2 NTAs is improved significantly under high field, which is nearly 8 times faster than that under low fields(40–60 V). The length and growth rate of the nanotubes are further increased with the increase of fluoride content in the electrolyte.展开更多
The highly ordered Ti O_2nanotubes(NTs) were fabricated by the anodic oxidation method.Their morphology,structure and crystalline phase were characterized by scanning electron microscopy(SEM) and X-ray diffractometer(...The highly ordered Ti O_2nanotubes(NTs) were fabricated by the anodic oxidation method.Their morphology,structure and crystalline phase were characterized by scanning electron microscopy(SEM) and X-ray diffractometer(XRD).The effects of morphology,specific surface area,pore structures and photocatalytic activity of the Ti O_2 NTs were investigated.UV–vis spectra analysis showed that its light absorption had been extended to the visible light range.The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic oxidation of gaseous HCHO and MB aqueous solution.The samples had better adhesion strength in the dark and showed a higher photocatalytic activity than nanoparticles.Especially,with ultraviolet light pretreatment,the nanotubes exhibited more stable active for photocatalytic decomposition and the photodecomposition rate remained at high level after 3 cycles of the photocatalysis experiment.Thus,how the number of surface active group ·OH increased and the mechanism for the great improvement for the photocatalytic activity are discussed.展开更多
Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil i...Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20%deionized water. Subsequently, g-C_3N_4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex. The results showed that g-C_3N_4 was successfully decorated on the TNTAs and the g-C_3N_4/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting. The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications.展开更多
TiO_(2) nanotube arrays,growing on three-dimensional(3 D)porous Ti membrane,were synthesized using a facile nonsolvent-induced phase separation and anodization process.The length of those three-dimensional nanotube ar...TiO_(2) nanotube arrays,growing on three-dimensional(3 D)porous Ti membrane,were synthesized using a facile nonsolvent-induced phase separation and anodization process.The length of those three-dimensional nanotube arrays could be tuned by prolonging the anodizing time.When the anodizing time is 8 h,the three-dimensional TiO_(2) nanotube arrays/porous Ti electrode exhibits well cycling stability and ultra-high specific capacity,which is used in lithium-ion batteries,attributed to the high utilization rate of the substrate and the high growth intensity of the active materials.Three-dimensional TiO_(2) nano tube arrays/porous Ti electrode,at 100μA·cm^(-2) with 8 h anodizing time,shows a typical discharge plateau at 1.78 V and exhibits the specific capacity with 2126.7μAh·cm^(-2),The novel nanotube arrays@3 D porous architecture effectively shortens the electron/ion transmission path,which could pave way for optimizing the design of highperformance anode materials for next-generation energy storage system.展开更多
基金supported by National 863 Program 2011AA050518the Natural Science Foundation of China(Grant Nos.11174197,11574203,and 61234005)
文摘Highly ordered TiO_2 nanotube arrays(NTAs) on Si substrate possess broad applications due to its high surfaceto-volume ratio and novel functionalities, however, there are still some challenges on facile synthesis. Here, we report a simple and cost-effective high-field(90–180V) anodization method to grow highly ordered TiO_2 NTAs on Si substrate,and investigate the effect of anodization time, voltage, and fluoride content on the formation of TiO_2 NTAs. The current density–time curves, recorded during anodization processes, can be used to determine the optimum anodization time. It is found that the growth rate of TiO_2 NTAs is improved significantly under high field, which is nearly 8 times faster than that under low fields(40–60 V). The length and growth rate of the nanotubes are further increased with the increase of fluoride content in the electrolyte.
基金financial support from Tianjin Science and Technology Support Plan Key Projects(NO.12ZCZDJC35600)
文摘The highly ordered Ti O_2nanotubes(NTs) were fabricated by the anodic oxidation method.Their morphology,structure and crystalline phase were characterized by scanning electron microscopy(SEM) and X-ray diffractometer(XRD).The effects of morphology,specific surface area,pore structures and photocatalytic activity of the Ti O_2 NTs were investigated.UV–vis spectra analysis showed that its light absorption had been extended to the visible light range.The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic oxidation of gaseous HCHO and MB aqueous solution.The samples had better adhesion strength in the dark and showed a higher photocatalytic activity than nanoparticles.Especially,with ultraviolet light pretreatment,the nanotubes exhibited more stable active for photocatalytic decomposition and the photodecomposition rate remained at high level after 3 cycles of the photocatalysis experiment.Thus,how the number of surface active group ·OH increased and the mechanism for the great improvement for the photocatalytic activity are discussed.
基金financial support from the National Natural Science Foundation of China (Nos. 51702025, 51574047)Natural Science Foundation of Jiangsu Province (Nos. BK20160277, BK20150259)
文摘Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20%deionized water. Subsequently, g-C_3N_4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex. The results showed that g-C_3N_4 was successfully decorated on the TNTAs and the g-C_3N_4/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting. The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications.
基金the National Natural Science Foundation of China(Nos.51801136,51701142 and 51871165)Tianjin Municipal Education Committee Scientific Research Projects(No.2017KJ075)the Australian Research Council Discovery Project(No.DP200100965)。
文摘TiO_(2) nanotube arrays,growing on three-dimensional(3 D)porous Ti membrane,were synthesized using a facile nonsolvent-induced phase separation and anodization process.The length of those three-dimensional nanotube arrays could be tuned by prolonging the anodizing time.When the anodizing time is 8 h,the three-dimensional TiO_(2) nanotube arrays/porous Ti electrode exhibits well cycling stability and ultra-high specific capacity,which is used in lithium-ion batteries,attributed to the high utilization rate of the substrate and the high growth intensity of the active materials.Three-dimensional TiO_(2) nano tube arrays/porous Ti electrode,at 100μA·cm^(-2) with 8 h anodizing time,shows a typical discharge plateau at 1.78 V and exhibits the specific capacity with 2126.7μAh·cm^(-2),The novel nanotube arrays@3 D porous architecture effectively shortens the electron/ion transmission path,which could pave way for optimizing the design of highperformance anode materials for next-generation energy storage system.