Preparation Of Fluorescent SnO₂/SnO₂-Au Nanoclusters And Their Application

SnO₂ is a very important N type semiconductor with many excellent performances such as photoelectric property,gas sensitivity and catalytic performance,SnO₂nanometer materials have been widely applied to many fields,for instance,transparent electrode,gas sensing device,photo electronic device,solar battery,anti-static coatings.Nanocluster meterials with a size similar to Fermi wavelength are made up of several or dozens of atoms,showing excellent activities of catalytic,magnetic and photoelectric property.Therefore,the preparation,characterization and utilization of SnO₂ nanometer materials have great siginificances.The main cotents were summarized as following:Firstly,SnO₂ fluorescent nanoclusters were prepared by main reacters SnCl₂ and H₂O₂ under UV irradiation,then on the baises of above-mentioned process,we added HAuCl₄ to prepare SnO₂-Au fluorescent nanoclusters with the condition of microwave heating.Fluorescence spectrum,AFM,SEM,XRD and XPS were employed to describe the structure and morphology of the two samples.Experiment res?Lts indicate that SnO₂ and SnO₂-Au nanoclusters have uniformly distributed,and the average particle size of SnO₂ NCs is 7 nm,the average particle size of SnO₂-Au NCs is 5 nm.the fluorescent color of SnO₂ NCs is blue??em=447 nm?.the fluorescent color of Au NCs is orange??em=447 nm?.Then,SnO₂ NCs as a photocatalyst was applied to degradate the p-nitrophenol?p-NP?and rodamine B?RhB?to explore the photocatalytic properties of SnO₂ NCs.Experiment res?Lts indicates that SnO₂ NCs shows excellent photocatalytic activity under UV irradiation,presents a potential application value in environmental sewage treatment field.But it can not degradate p-nitrophenol and rodamine B obviously under the visible light,it is because that SnO₂ has stronger transmissive ability under visible light,and existing strong absorption band in the?Ltraviolet region.A further reaserch shows that cavitation and hydroxyl radicals of small size SnO₂ NCs are the main active species in the degradation reaction.Lastly,SnO₂-Au NCs and SnO₂ NCs were conceived as fluorescent probs to establish fluorescence spectral sensor to detect berberine hydrochloride?BHC?and copper ions(Cu²⁺).The fluorescence of orange fluorescent SnO₂-Au NCs decreased upon increasing the concentration of BHC,it is also found that the fluorescence intensity has good relationship with the concentration in the range of 1.0×10^-61.0×10^-4 mol L^-1,(I_F0-I_F)/I_F=-1.1081+0.07681c,and the detection limit?3?/k?is 7.5×10^-8mol L^-1.It turns to be that this method can be used in the detection of BHC in real drug.SnO₂-Au NCs with two fluorescent emission wavelengths can be prepared by controling the experiment conductions to be utilized to detect copper ions.Experimental res?Lts show that The fluorescence of orange fluorescent SnO₂-Au NCs decreased upon increasing the concentration of Cu²⁺and have a good relationship with the concentration of Cu²⁺in the range from5×10^-71.5×10^-5 mol L^-1,(I_F0-I_F)/I_F=-1.1081+0.07681c.and the detection limit?3?/k?was 3×10^-7mol L^-1 In summury,SnO₂-Au NCs can be used to detect Cu²⁺and BHC as a simple and accurate means and can be used in detection of actual samples.