| With the advancement of science and technology and the development of society,a series of environmental problems have attracted more and more attention.The use of clean energy and the degradation of environmental pollutants have gradually become a technology that we need to master.Titanium dioxide(TiO2)is a common semiconductor metal oxide with the advantages of low cost,non-toxicity and good stability,and has broad application prospects in the direction of environmental protection and new energy.Titanium dioxide photocatalytic technology can not only be used to split water to generate hydrogen,but also can effectively reduce organic pollutants,which has become a research hotspot because of its universal applicability.However,the limitations of titanium dioxide materials are also obvious.The large band gap(Eg)and the high recombination rate of photogenerated electrons(e-)and holes(h+)make the light absorption of titanium dioxide itself only limited to the ultraviolet light with small wavelength.At the same time,the efficiency of generating active factors is not high,so it is urgent to optimize the modification of titanium dioxide materials.There are many strategy to optimize material’s photocatalysis performance.In this paper,anatase titanium dioxide nanosheets(TiO2 NS)were grown on FTO by hydrothermal synthesis,which showed anisotropy on different crystal planes,and on this basis,the second phase material was deposited to conduct heterojunction.Constructed,prepared a synergistic body of crystal plane heterojunction and heterojunction between two substances,enhanced the photocatalytic activity of titanium dioxide,and explored the reasons for its optimized performance.The main contents are as follows:(1)TiO2 NS with exposed specific crystal planes was prepared by hydrothermal synthesis,and then metal palladium Pd and metal oxide CoOx were deposited on different crystal planes of the TiO2 NS by photodeposition to find an optimal deposition time and the rational density of the second and the third phase material,the growth and deposition of the sample was observed by X-ray diffraction(XRD),scanning electron microscope(SEM),transmission electron microscope(TEM),UV-Vis diffuse reflection(UV-vis)test,electrochemical impedance spectroscopy(EIS)test,chronoamperometry(It curve)test,Mott-Schottky test,etc.proved that the optimized TiO2 NS has a larger light absorption range and carrier separation ability,it has stronger visible light responsiveness and photocatalytic activity.We test our samples at the same voltage,in comparison with P25,which sample measured 25 μA/cm2,our optimized sample has better photocurrent density about 102 μA/cm2.(2)After the TiO2 NS with exposed specific crystal planes was fabricated by hydrothermal synthesis,the second phase MoS2 was grown on the original TiO2 NS by secondary hydrothermal growth and photodeposition,respectively.By controlling the growth time of the second phase,the photoelectric Chemical tests were carried out to obtain the most reasonable amount of second-phase deposition.The growth and deposition of the samples were observed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and transmission electron microscopy(TEM),and UV-visible diffuse reflectance(UV-vis)test,electrochemical impedance spectroscopy(EIS)test,chronoamperometry(It curve)test,Mott-Schottky test,etc.prove that the optimized TiO2 NS has a larger light absorption range and carrier separation ability,selectively deposited sample has a better charge separated ability. |
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