Solution-systhesis And Photocatalytic Property Studies Of Semimetallic Bismuth Miro/nano-materials

Compared with bulk materials,Bi based nanomaterials have been widely used in very broad areas due to their unique properties,such as optoelectronics,catalysis,information storage and so on.It is well known that properties of Bi based nanostructures are strongly dependent on their composition,morphology,dimension,crystallinity,shape and construction geometry.In addition,the shape tunable synthesis has received considerable attention recently because varying the morphology of Bi based nanostructures allows one to fine-tune their properties over a wide range.In this thesis,Bi based nanostructures with different morphologies including bismuth microsphere,Bi/BiOCl hollow microsphere,flower-like structure and ellipsoid-like structure were successfully prepared via a low-temperature liquid-phase synthesis method.The morphologies of Bi based nanomaterials can be adjusted by changing surfactants,reaction temperature,organic molecules and so on.What’s more,the nanomaterials will be used for photocatalystic degradation of organic materials(such as RhB,MO and BPA).The thesis consists of three parts:First,3D microspheres of Bi based nanostructures with tunable morphologies were obtained with bismuth,NaCl,hydrazine hydrate,CTAB as bismuth source,assistant agent,reducing agent,surfactant respectively,which the precursor were first synthetized at 25℃,and Bi samples were reduced in alkaline environment at 90℃.The morphology of Bi based nanomaterials can be adjusted by changing the reaction temperature,the amount of reducing agent,and the type of surfactant.Furthermore,the experiment of photocatalytic degradation of organic materials(RhB,MO,BPA)was carried out with different morphologies of Bi based microsphere as catalysts,the experiments demonstrated that 3D microspheres of Bi based nanostructures possessed excellent catalytic properties.What’s more,the experiment of photocatalytic degradation of RhB was carried out at different pH,we found that the microspheres manifested excellent photocatalytic activity under visible light by controlling the pH value to some extent.Second,Bi/BiOCl hollow microspheres were successfully synthesized in alkaline solution with bismuth chloride,NaCl,hydrazine hydrate,PVP K13 as bismuth source,assistant agent,reducing agent,surfactant respectively,which the precursor were first synthetized at 25℃,and Bi/BiOCl hollow microspheres samples were reduced in alkaline environment at 80℃.The morphology of Bi nanostructures can also be adjusted by changing the reduction time,the reaction temperature,the amount of reducing agent and the type of surfactant.In addition,the experiment of photocatalytic degradation of RhB was carried out with Bi/BiOCI hollow microsphere with different reduction time as catalysts,the experiments demonstrated that Bi/BiOCl hollow nanostructures with the reduction time of 3 h.possessed excellent catalytic properties.Third,flower-like and ellipsoid-like Bi based nanostructures with tunable morphologies were prepared with bismuth chloride,NaCl,hydrazine hydrate,PVP K30 as bismuth source,assistant agent,reducing agent,surfactant respectively at 90℃,which were prepared with different organic molecules(trisodium citrate dihydrate and ethylene glycol)as controlling agent.The morphology of Bi nanostructures can also be adjusted by changing the amount of organic molecule,the reaction temperature,the amount of NaCl,the amount of N2H4·H2O and reduction time.In addition,the experiment of photocatalytic degradation of RhB was carried out with different morphologies of Bi based nanomaterials as catalysts,the experiments demonstrated that assembly morphology of Bi based nanostructures possessed excellent catalytic properties.