Synthesis And Properties Of Titanium Dioxide Based Composites

In this paper,titanium dioxide has been deposited on FTO via hydrothermal method.Further,carbon nitride/titania composite films have been deposited by chemical vapor deposition,in this process a layer of carbon nitride was deposited on the surface of titanium dioxide nanoarrays.In addition,carbon nitride/titania composite catalysts were prepared by spray drying and following calcination.The crystal structures and morphologies of the obtained samples were characterized using XRD and SEM,respectively.The optical properties of the obtained samples have been investigated by DRS and PL.The properties of as-prepared samples have been investigated,such as photoelectrochemical catalytic water splitting to hydrogen evolution,photoelectrocatalytic and photocatalytic decomposition of organic dyes.The main research contents are as follows:1?Titanium dioxide nanoarrays have been successfully deposited on FTO by hydrothermal method using titanium???sulfate.The concentration of titanium sulfate has a significant effect on the morphologies of titanium dioxide nanoarrays.With the increase of the concentration of titanium sulfate,the nanoarray initially consists of a uniform conical array,then becomes a columnar nanoarray and spike-like large particles.Titanium dioxide nanoarrays have a directional growth tendency,and the directional growth tendency is also related to the concentration of titanium sulfate.In addition,for hydrogen production and photodegradation of organics were tested.The results show that the nanoarray prepared by 0.05 mol/L titanium sulfate has the best photoelectrochemical properties.Its maximum photocurrent is 0.55 mA/cm².2?The carbon nitride/titania dioxide composite films were synthesized through chemical vapor deposition.The visible light absorption of The carbon nitride/titania dioxide composite films were significantly enhanced.The effects of different vapor deposition temperatures on the performance of photoelectrode are discussed,the unloaded photoelectrode showed best performance at 500?and Photocurrent density was 2.03 times of that unloaded Titanium dioxide nanoarrays photoelectrode.At the same time,it also showed the best photodegradation of Rhodamine B performance,the photodegradation rate of Rhodamine B is nearly 100%for 60 min.TiO₂ films compositing with g-C₃N₄ can improve not only the performance of the spectrum absorption but also the efficiency of the photoelectrocatalytic degradation for organic dyes.3?g-C₃N₄/TiO₂?B?composites were prepared by spray drying and following calcination.EIS,Mott-Schottky plots,and current density-time?I-t?curves were gained by means of electrochemical workstation.The composites were evaluated as photocatalysts for Rhodamine B decomposition in aqueous solution.Experimental result showed that the photocatalytic activity of g-C₃N₄/TiO₂?B?is obviously higher than that of TiO₂?B?.The g-C₃N₄/TiO₂?B?composite with loading g-C₃N₄ showed much high photocatalytic performance for degradation of Rhodamine B.After 5 cycles experiments,the photocatalytic efficiency of g-C₃N₄/TiO₂?B?is still as high as initial.