Supported CuPd Alloy Nanoparticles As Efficient Photocatalysts For Suzuki Coupling Reaction Under Visible Light Irradiation

Today,the conversion of solar energy into chemical energy is a very popular research field,because it can solve both the energy and environmental problem at the same time.Photocatalytic technology has a great development prospect in the field of green chemistry,and the research on photocatalysis has been studying for several decades.At present,the application of photocatalytic technology is mainly in water splitting,environmental purification and organic synthesis,etc.In this paper,we do some research on the application of photocatalytic technology in the field of organic synthesis.We have synthesized a series of supported CuPd alloy nanoparticle photocatalysts,and applied them to the Suzuki coupling reaction at room temperature.Our research contents and results are shown as follows:1)We prepared g-C₃N₄ and C as two kinds of catalyst supportment,we prepared supported CuPd alloy nanoparticles with different proportions of copper and palladium through reduction-impregnation method,and we prepared respectively TiO2,ZrO2,g-C₃N₄,C supported copper-palladium alloy nanoparticles through the same method as above.2)We conducted a series of characterization of the prepared supported copper palladium alloy nanoparticles,including the X ray energy spectrum?EDS?,transmission electron microscopy?TEM?,X ray photoelectron spectroscopy?XPS?,ultraviolet visible absorption spectroscopy?UV-Vis?.The results show that the CuPd alloy nanoparticles prepared by our method have formed an alloy structure.3)We selected the Suzuki coupling reaction to test the photocatalytic performance of the catalyst.We selected p-bromophenylmethylether and phenylboronic acid as template of reactants,and further the reaction conditions,including solvent,reactant concentration,reactants ratio,reaction time,base and reaction atmosphere conditions were optimized.4)The photocatalytic activity of photocatalyst was tested under different light intensity and wavelength conditions,we found that when we increase the intensity of incident light or using the light source with shorter wavelength,the supported copper-palladium alloy nanoparticles enhanced photocatalytic activity,The dependence of photocatalytic activity on light intensity and wavelength indicates that energetic electrons excited by light absorption are responsible for the observed photocatalytic activity.5)In order to test the applicability of the photocatalyst,we carried out the photocatalytic experiments on the reactant molecules with different substituents.The results show that the supported CuPd alloy nanoparticles have high photocatalytic activity for majority of the Aryl halides in Suzuki coupling reaction.6)We have tested the Reusability of supported copper-palladium alloy nanoparticles for Suzuki coupling reaction.It is found that the catalyst still maintains a high activity after four cycles?conversion > 97%?.