| With promising application prospect in solving environmental pollution,semiconductor photocatalysts have recently attracted wide attention.As a new type of semiconductor,Nb3O7 F photocatalyst may be widely used because of its similar electronic & band structure with Ti O2,good light-corrosion resistance and low carrier recombination rate.However,two key issues,preparation process and spectral absorption,restrict its further practical application.In this dissertation,Nb3O7 F nanomaterials were successfully synthesized by hydrothermal method and the thermal stability was studied in detail.Meanwhile,nanocrystallization technology and hybrid methods were used to promote the spectral absorption.The research contents are included as follows:1.The thermal stability of Nb3O7 F was studied by a static thermal analysis.The results show that Nb3O7 F exhibits good thermal stability when the heat-treated temperature is below 400 oC.Over 500 oC,part of Nb3O7 F decomposes and Nb3O7F/Nb2O5 hybrids can be obtained finally.Owing to good synergistic between Nb3O7 F and Nb2O5,the hybrids exhibit better carrier transport and higher photocatalytic activity than pure Nb3O7 F.2.Two-phase-coexistence Nb3O7 F nanoparticals were firstly synthesized through a solvothermal method with silk as template.Al element originating from silk was introduced into Nb3O7 F structure during the preparation process.As a result,two-phase coexistence structures were crafted by lattice deformation induced by Al impurity and structural rearrangement.Consequently,two-phase-coexistence Nb3O7 F possesses higher spectrum response and photocatalytic activity.3.Nb3O7F/XS2(X=Mo,W)hybrids were synthesized through a two-step hydrothermal method assisted by ultrasonic exfoliation.It can be found that absorption edge of Nb3O7F/XS2 hybrids shows obvious red shift.Besides,band structure and carrier transport of Nb3O7F/XS2 are optimized markedly.Importantly,the photocatalytic reaction rate is three times more than that of pure Nb3O7 F. |
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