The nitrogen-doped porous TiO2 layer on Ti6Al4V substrate was fabricated by plasma-based ion implantation of He, O and N. In order to increase the photodegradation efficiency of TiO2 layer, two methods were used in th...The nitrogen-doped porous TiO2 layer on Ti6Al4V substrate was fabricated by plasma-based ion implantation of He, O and N. In order to increase the photodegradation efficiency of TiO2 layer, two methods were used in the process by forming mesopores to increase the specific surface area and by nitrogen doping to increase visible light absorption. Importantly, TiO2 formation, porosity architectures and nitrogen doping can be performed by implantation of He, O and N in one step. After implantation, annealing at 650 ℃ leads to a mixing phase of anatase with a little rutile in the implanted layer. By removing the near surface compact layer using argon ion sputtering, the meso-porous structure was exposed on surfaces. Nitrogen doping enlarges the photo-response region of visible light. Moreover, the nitrogen dose of 8×1015 ion/cm2 induces a stronger visible light absorption. The photodegradation of rhodamine B solution with visible light sources indicates that the mesopores on surfaces and nitrogen doping contribute to an apparent increase of photocatalysis efficiency.展开更多
The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reducti...The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 catalysts.The catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction.The results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1.展开更多
基金Supported by the National Natural Science Foundation of China(No.21477050,No.21522603,No.21706101)the Henry Fok Education Foundation(No.141068)+2 种基金the Six Talents Peak Project in Jiangsu Province(No.XCL-025)the Chinese-German Cooperation Research Project(No.GZ1091)the China Postdoctoral Foundation(No.2017M611731)~~
基金Project(20040213048) supported by the Specialized Research Fund for the Doctoral Program of Higher Education of ChinaProject(20090450737) supported by the China Postdoctoral Science Foundation
文摘The nitrogen-doped porous TiO2 layer on Ti6Al4V substrate was fabricated by plasma-based ion implantation of He, O and N. In order to increase the photodegradation efficiency of TiO2 layer, two methods were used in the process by forming mesopores to increase the specific surface area and by nitrogen doping to increase visible light absorption. Importantly, TiO2 formation, porosity architectures and nitrogen doping can be performed by implantation of He, O and N in one step. After implantation, annealing at 650 ℃ leads to a mixing phase of anatase with a little rutile in the implanted layer. By removing the near surface compact layer using argon ion sputtering, the meso-porous structure was exposed on surfaces. Nitrogen doping enlarges the photo-response region of visible light. Moreover, the nitrogen dose of 8×1015 ion/cm2 induces a stronger visible light absorption. The photodegradation of rhodamine B solution with visible light sources indicates that the mesopores on surfaces and nitrogen doping contribute to an apparent increase of photocatalysis efficiency.
基金Project supported by the National Natural Science Foundation of China(21876168)the Key Projects for Common Key Technology Innovation in Key Industries in Chongqing(cstc2016zdcy-ztzx0020-01)+1 种基金Youth Innovation Promotion Association CAS(2019376)the Graduate Innovation Project of Chongqing Technology and Business University(yjscxx201803-028-22)。
文摘The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 catalysts.The catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction.The results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1.
