| ZnO has strong redox ability,stable photochemical properties,simple preparation process,and has the dual characteristics of piezoelectric and photocatalysis,but its photogenerated carriers separation efficiency is low and it is difficult to recover in the process of degarading pollutants.ZnO nanorods are grown on the surface of the inner wall of porous ceramics,and the energy impact generated by the complex flow of water in the three-dimensional porous structure causes the ZnO nanorods to deform,forming a periodic built-in electric field to continuously separate the photogenerated carriers,which can improve their photocatalysis performance,while solving the problem of ZnO recycling.Therefore,hydrothermal methods were used to grow ZnO nanorod arrays on the surface of Al2O3 through-hole ceramics with small,dense and regular channels and Zr.2 foam ceramics with irregular channel structures.The composition and microstructure of ZnO NRs were characrerized by means of XRD,SEM and TEM.By adjusting the stirring rate,the flow state of the water in the two porous structures was analyzed to explore the change of the photocatalytic performance,and the mechanism of the deformation of the ZnO nanorods caused by the flow state of the water in different carriers and the improvement of its photocatalytic performance was revealed.Al2O3 through-hole ceramics were prepared by sodium alginate ion gel method using 5wt%A12O3 as raw material and tert-butanol solution as solvent.The sample has a small and dense pore structure and high specific surface area,the pore size distribution is 100-200?m.The pore wall is thin and high in strength.The pore structure in the cross-section is highly ordered and the open porosity reaches more than 80%.Using this as a substrate,ZnO NRs are grown by hydrothermal method.When the thickness of the ZnO seed layer is 600 layers,the length-to-diameter ratio of the ZnO nanorods is moderate,which is suitable for the pore diameter of the ceramic substrate.As the stirring rate increases,the degradation efficiency of ZnO NRS/Al2O3 the through-hole ceramic to MO solution also increases,which proves that the small-pore porous structure of the Al2O3 through-hole ceramic can improve the piezoelectric photocatalytic activity of ZnO NRs The photocatalytic performance of ZnO NRS/Al2O3 through-hole ceramics is 36%higher than unsupported ZnO NRsZnO NRs were grown on ZrO2 foam ceramics with irregular pore structure by hydrothermal method.The effect of seed layer thickness on ZnO morphology was studied.The mechanism of water flow impact on the photocatalytic performance of ZnO NRs/ZrO2 foam ceramics was analyzed.The results showed that when the thickness of the seed layer is 200,the gap between the nanorods is moderate and the length is uniform.The increase of the stirring rate is beneficial to promote the separation and migration of ZnO NRs carriers.The highest degradation rate of MO solution can reach 70%,compared with the two-dimensional FTO substrate and Al2O3 through-hole ceramic substrate,ZrO2 foam ceramics has a complex and tortuous three-dimensional space connecting pore structure and irregular arc surface,which is more conducive to chang the state of water flow.The irregular porous arc surface structure will form eddy currents with different energy levels,which can frequently contact and collide with ZnO NRs to stimulate their piezoelectric properties to a greater extent and promote the separation of photo-generated carriers.Greatly improve the piezoelectric photocatalytic activity of ZnO NRs... |
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