Fabrication Of Photoelectrocatalytic Devices Based On Printing Technology And Their Performances In The Degradation Of Methylene Blue(MB)

The emissions of industrial wastewater containing a large number of organic pollutants have brought environmental pollution and health problems to humans which need to be solved urgently.As one of the organic pollutant treatment methods,photocatalytic technology has been receiving increasing attention because it has the advantages of low cost,environmental friendliness,and the ability to completely degrade organic pollutants.At present,the focus of photocatalytic researches is mainly on the improvement of photocatalysts performance,while there is less research on photocatalysis from the perspective of the combination of photocatalytic optoelectrical materials and devices.In this dissertation,aerogel patterned comb-shape electrode photoelectrocatalytic devices with rGO/TiO₂ as the catalyst system via 3D direct-writing inkjet printing technology have been fabricated.The influence of ink printing parameters on the patterning of printing devices have been examined.On this basis,comb-shape electrode devices were prepared on a slide glass and a flexible PET film substrate,respectively.And the photocatalytic performance of degradation of methylene blue by the as-prepared devices was investigated.The structure-activity relationship between the patterning of printed catalyst device and catalytic performance were explored.The main research content is as follows:1)Graphene oxide?GO?was prepared by modified Hummers method.GO ink and GO/TiO₂ ink were successfully prepared by hydrothermal method.The optimal printing condition parameters were investigated in terms of needle inner diameter,pressure and line speed.It was found that as the increase of inner diameter of the needle,the improvement of printing pressure,or the decrease of printing line speed,the line width of the printed line gradually becomes larger.The optimized printing parameters were0.41 mm of needle inner diameter,10.0 psi of pressure,and 15.0 mm/s of line speed.Under these optimized print parameters,the rGO/TiO₂ aerogel patterned comb-shape electrodes were printed.2)With the characterizations of SEM,TEM,AFM,XRD,FTIR,Raman and XPS,it was confirmed that the as-synthesized rGO/TiO₂ patterned comb-shape electrodes have three-dimensional porous structures,in which the three-dimensional rGO was closely integrated with the TiO₂ particles.The photoelectrocatalytic methylene blue?MB?degradation performance of the comb-shape electrodes was investigated,and the structure-activity relationships between the patterned comb-shape electrodes with different amounts of comb-fingers and the catalytic activity and photoelectric properties were also analyzed.It was found that the activities of the patterned comb-shape electrode devices were higher than that of the unpatterned one.And the activities of the comb-shape electrodes were enhanced with the increase of patterned comb-fingers.Combing with the characterizations,it could be deduced that the patterned comb-fingers would promote the effective mass transfer of reaction species and the charge transfer efficiency of catalysts which could further enhance the light response.3)The photoelectrocatalytic MB degradation performance and flexural stability of rGO/TiO₂ flexible comb-shape electrodes were also investigated.The results show that the flexible comb-shape electrodes have good photoelectrocatalytic activity,and can maintain good activity and bending resistance in the bending angles from 0 to 20°.