The effect of TiO2 on the crystallization behaviors of the glass ceramics prepared from granite tailings was investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD), and field emission sca...The effect of TiO2 on the crystallization behaviors of the glass ceramics prepared from granite tailings was investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The results showed that the crystallization peak temperature decreased firstly, and then increased with the increase of TiO2 content. The optimum addition amount of TiO2 was 8 wt%. With a single-step heat treatment at 924 ℃ for I h, augite precipitated as the only crystalline phase both on the surface and in the interior. The avrami parameter of the sample was 3.25, suggesting a two- dimensional crystallization mechanism. The activation energies for phase separation and crystallization of augite were 321.75 and 698.83 kJ/mol, respectively.展开更多
CdS quantum dots(QDs) sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays(TNAs) were...CdS quantum dots(QDs) sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays(TNAs) were synthesized on Ti foils by anodic oxidation method. Then CdS quantum dots were deposited onto the TiO2 nanotube arrays by successive ionic layer absorption and reaction(SILAR) method to serve as the sensitizers. Cd(NO3)2 and Na2S were used as the precursor materials of Cd+ and S2- ions, respectively. It is found that the CdS QDs sensitizer may significantly increase the light response of TiO2 nanotube arrays. With increasing CdS QDs deposition cycles, the visible light response increases. Maximum photocurrent was obtained for the QDs that have an absorption peak at about 500 nm. Under AM 1.5 G illuminations(100 mW cm^-2), a 4.85 mA/cm^2 short circuit current density was achieved, and the maximium energy conversion efficiency of the asprepared CdS QDs-sensitized TNAs solar cells was obtained as high as 0.81% at five SILAR cycles.展开更多
基金Funded by the National Key Technology Support Program of China(No.2012BAA10B03)Hubei Provincial Science and Technology Department,China(No.2012BAA1001)
文摘The effect of TiO2 on the crystallization behaviors of the glass ceramics prepared from granite tailings was investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The results showed that the crystallization peak temperature decreased firstly, and then increased with the increase of TiO2 content. The optimum addition amount of TiO2 was 8 wt%. With a single-step heat treatment at 924 ℃ for I h, augite precipitated as the only crystalline phase both on the surface and in the interior. The avrami parameter of the sample was 3.25, suggesting a two- dimensional crystallization mechanism. The activation energies for phase separation and crystallization of augite were 321.75 and 698.83 kJ/mol, respectively.
基金Funded by Major State Basic Research Development Program of China (973 Program) (No.2009CB939704)Key Project of Chinese Ministry of Education (No.309021)
文摘CdS quantum dots(QDs) sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays(TNAs) were synthesized on Ti foils by anodic oxidation method. Then CdS quantum dots were deposited onto the TiO2 nanotube arrays by successive ionic layer absorption and reaction(SILAR) method to serve as the sensitizers. Cd(NO3)2 and Na2S were used as the precursor materials of Cd+ and S2- ions, respectively. It is found that the CdS QDs sensitizer may significantly increase the light response of TiO2 nanotube arrays. With increasing CdS QDs deposition cycles, the visible light response increases. Maximum photocurrent was obtained for the QDs that have an absorption peak at about 500 nm. Under AM 1.5 G illuminations(100 mW cm^-2), a 4.85 mA/cm^2 short circuit current density was achieved, and the maximium energy conversion efficiency of the asprepared CdS QDs-sensitized TNAs solar cells was obtained as high as 0.81% at five SILAR cycles.