Construction Of Sulfide Modified By Conductive Polymers And Their Photocatalytic Activities In Removal Of Cr(?)

As a ubiquitous renewable energy source,the brilliant sun has stored a rich source of energy for the planet.Semiconductor photocatalytic technology has a very important research significance as a new technology that can directly use natural light to solve environmental problems in chemical reactions.However,traditional sulfide semiconductors have the characteristic such as weak environmental stability and fast carrier recombination,which have greatly hindered the application and development of traditional sulfide semiconductors.Therefore,exploring a suitable method to prepare a wide light absorption range,fast carrier migration rate and higher environmental stability is the basis for ensuring the large-scale use of photocatalytic technology.In this dissertation,organic semiconductor-modified metal sulfides are used to design and prepare high-activity,stable and broad-spectrum response photocatalytic materials,and to further enhance the light absorption range and stability of traditional sulfide photocatalysts.On this basis,based on the analysis of the photocatalytic performance,chemical physical structure and other data of the prepared materials,the root cause of the performance improvement was studied in depth,and the stability was proved to be greatly improved.In this paper,the in-situ loading method is used to adjust the content of the supporting material to increase the light absorption range and carrier migration rate of the sulfide.Based on the research on the photocatalytic performance,the fundamental reasons affecting the photocatalytic performance are fully studied to further Promote the catalytic activity of composite materials;simple preparation of catalysts through simple thermal evaporation methods,and used for the degradation of other environmental pollutants?2-mercaptobenzothiazole?,in order to achieve the multifunctional catalyst.The research content of this article is as follows:1.A wide spectrum response?UV-Vis-NIR?polypyrrole?PPy?modified hexagonal SnS₂ nanosheet composite was designed by in-situ polymerization and applied to photocatalytic reduction of Cr???.The light absorption range,carrier migration rate and environmental stability have been studied in depth.The experimental results proved that 15-PPy/SnS₂ shows the best catalytic activity,which is 3.33 times that of the pure SnS₂.The introduction of PPy could greatly broaden the light absorption region and further improve the light absorption intensity of SnS₂,so that the composite material not only has better light absorption intensity in the visible light region???420 nm?,but also exhibits excellent photocatalytic performance in the near infrared region???760 nm?.2.A novel 3D PPy/Zn₃In₂S₆ nanoflower composite was successfully fabricated via in-situ polymerization.The results show that 5%PPy/Zn₃In₂S₆ exhibits superior photocatalytic activity with almost 100%Cr???reduction just within 24 min and99.4%of Methyl orange?MO?is degraded in 25 min.On this basis,factors of different catalyst dosage,concentration,different ions and pH under the reduction system were systematically investigated.Especially,different organic acids were in-depth analyzed and the activity could be significantly enhanced just adding 0.1mmol organic acids.The results show that in the photoreduction of Cr???,the functional groups?-OH,-COOH?,pH and other ions also have a very important influence on the photocatalytic activity.The results indicates that both-OH and-COOH in organic acids are conducive to the improvement of photocatalytic Cr???reduction performance,and-OH exhibits a superior improvement performance compared to-COOH.3.The PANI/Zn₃In₂S₆ nanoflower composite was prepared by electrostatic adsorption method,which improved the photocatalytic reduction of Cr???and the degradation efficiency of 2-mercaptobenzothiazole?MBT?.0.05%PANI/Zn₃In₂S₆shows the best activity.It is 3.76 times?Cr????and 3.27 times?MBT?than that of Zn₃In₂S₆ in the visible light region???420 nm?,and it shows excellent Cr???reduction performance in??550 nm.On this basis,the effects of organic acids and pH on photocatalytic reduction of Cr???were studied.By mass spectrometry,the intermediates obtained by degrading MBT have been fully studied.The results show that PANI excellent light absorption and electron transport capabilities effectively enhance the catalyst's light absorption performance and carrier migration rate.