Preparation Of Visible Light Responsive Catalyst Based On MIL-53(Fe) And Its Catalytic Performance For Oxidation Of Alcohols

As a sustainable energy source,solar energy can be effectively used and converted it into various forms of energy to achieve its collection and utilization by photocatalytic technologies.This view is also in line with the environmental requirements nowadays,which can reduce pollution and avoid waste of natural resources.Therefore,it is particularly important to use photocatalytic technology to realize the storage,conversion and utilization of solar energy.Develop of new photocatalysts is the key to achieve this goal.The use of metal-organic frameworks?MOFs?to prepare novel photocatalysts has become a hot research topic.The harsh reaction conditions in the traditional organic synthesis process are not conducive to large-scale industrial.The advantages of mild photocatalytic organic reaction conditions,efficient operability,clean energy and high product selectivity of the photocatalysis could solve these problems.This paper designed and synthesized three new types of photocatalyst and applied it to photocatalytic organic reactions.With the catalysis of the synthesized photocatalysts under visible light,many of the arophatic alcohol were coverted to the correspounding carbory compounds with high efficiency.The possible reaction mechanism of the photocatalysis reactions was also further invertied.The research content of this paper is as follows:1.A series of PDA/MIL-53?Fe?composite photocatalysts with different ratios of PDA to MIL-53?Fe?were prepared with natural simulation methods.The experimental results show that due to the excellent electron accepting ability of PDA,the transfer efficiency of photogenerated electrons could be effectively improved.Compared with the sole PDA and MIL-53?Fe?,the composite photocatalyst had better catalytic performance under identical conditions.The results of activity species capture experiment showed that the photocatalytic process was a direct holes oxidation.The results of the cycle experiments revered that the photocatalyst had excellent photostability.2.Following the work of the first part,in order to further improve the efficiency of the oxidation,Eu,a rare earth element,was doped into the inorganic semiconductor?ZnO?to macle the Eu-doped ZnO/MIL-53?Fe?nanocomposite photocatalysts through in-situ synthesis.The structure,morphology and photoelectric properties of the namicomposites were characterized via XRD,FT-IR,SEM,UV-Vis DRS,PL,EIS and so on.The experimental results showed that the introduction of Eu could greatly improve the photocatalytic performance of the composite.The results of mechanism studies showed that the selective oxidiation of benzalcohol was dominated by two active species,h⁺and·OH.The photocatalyst also has good photostability in the oxidation.3.In order to reduce the costs of the photocatalyst,low-cost Ni₂P is used as a cocatalyst to prepare different proportions of Ni₂P/MIL-53?Fe?nanocomposites photoelectric through one-step hydrothermal method.The structure,morphology and optical properties of the nanocomposites were characterized by XRD,FT-IR,SEM,UV-Vis DRS,PL,EIS and so on.The experimental results showed that the introduction of Ni₂P could further improve the photocatalytic efficiency of MIL-53?Fe?.The results of the mechanism study showed that the photocatalytic process which was the selective oxidation process was carried out by the species of h⁺.