Mild Solvothermal Syntheses,Characterizations And Physical Properties Of New Quaternary Two-Dimensional Chalcogenidoarsenates

Multinary chalcogenides are kinds of semiconductors with excellent physical and chemical properties,which have been widely used in the field of nonlinear optics,photocatalysis,solar cells and so on.Therefore,the synthesis of these materials has become a very important and popular field of inorganic synthetic chemistry.In recent years,multinary chalcogenidoarsenates have attracted more and more attentions due to their rich structural characteristics and many potential applications.It is well known that surfactants with low vapor pressure,high thermal stability and low cost have been widely used in synthesis of nanocrystals and porous materials because they can be used to tune the size,surface energy and physical properties of nanocrystals,and control the pore size of porous materials.However,there are few reports on using surfactants to explore multinary chalcogenidoarsenates.In this dissertation,surfactants and organic amines were employed as the reaction media,by adjusting the reaction conditions(the kind and amount of reactants and solvents,reaction temperature and reaction time),six new quaternary chalcogenidoarsenates:CS3CuAs4S8(1),Cs3CuAs4Se8(2),NaAg2AsS3·H2O(3),KAg2AsS3(4),CS2Ag2AS2S5(5)and Cs3AgAs4S8(6)were successfully synthesized.The synthesis is facile,the yield is high and crystal quality is good.The crystal structures and physical properties of these compounds were characterized by SEM,EDS,single crystal X-ray diffraction,XRD,UV,TG and theoretical calculations in detail.It was found that these six chalcogen compounds all exhibit a 2D layered structure,and only NaAg2AsS3·H2O was an indirect band gap semiconductor while the others were direct band gap semiconductors.