Development And Application Of New Visible Light Catalysts

After entering twenty-first Century,the energy resources that human beings can develop have been seriously insufficient,and a large number of environmental pollution problems are from the use of energy,which have seriously affected the survival of mankind.Compared to other fossil fuels,solar energy is a great wealth of nature,it is rich in reserves,clean and safe,cheap and easy to get.Now researchers both at home and abroad pay more attention to the semiconductor photocatalysis solar excitation,the technology can not only solve the energy problem,making water split to hydrogen under solar energy driven;also can solve environmental problems,degradating organic pollutants into carbon dioxide and water.Therefore,the semiconductor photocatalytic technology is regarded as one of the most potential applications of solar energy technology.In this paper,we use g-C₃N₄,ferrous oxalate,BiOI as catalyst,degrading methyl orange and rhodamine B under visible light,through our research and innovation,they have good photocatalytic properties under visible light.Only using bulk graphitic carbon nitride?g-C₃N₄?as photocatalyst,methyl orange was hardly degraded under visible light,while adding a small amount of oxalic acid into the g-C₃N₄ catalyst system,methyl orange was rapidly completely degraded within a short time.To combine oxalic acid into bulk g-C₃N₄ system highly enhanced g-C₃N₄ photocatalytic performance for methyl orange degradation.This probably implies that the g-C₃N₄ system with oxalic acid has the potential to produce H2O2 from molecular oxygen.Using ferrous oxalate as a catalyst for the degradation of rhodamine B and methyl orange in oxalic acid assisted,we found that in the presence of oxalic acid,the photodegradation rate can be greatly improved.Therefore,we also analyze its photocatalytic mechanism,and it is considered that oxalic acid is to be a efficient sacrifice factor.We reported a facile route to prepare ?-ferrous oxalate dihydrate layered nanosheets using ferrous sulfate and oxalic acid by simple mechnochemical?grinding?method and convert to ?-FeOx by aging treatment at 100 ? for 10 h.Their photocatalytic performances were evaluated by the degradation of rhodamine B under visible-light illumination.It was found that both were efficient photocatalysts.It is found that by mediation of sodium acetate,all of the obtained BiOI in different solvent system are tiny and thin BiOI nanoplates,which relative intensity ratios of the?110?/?102?reflection in XRD patterns are much larger than the standard values in the JCPDS card no.10-0445,indicating preferential orientation growth in the?110?direction.And their photocatalytic performance for degradation of methyl orange?MO?under visible light illumination are higher than that of without mediation of sodium acetate.Thus,this provides a new route to prepare BiOI nanoplates with exposed {001} facet and high photocatalytic activity.