This study systematically studied the effects of Pr,Fe,and Na as representative rare earth,transition,and alkali metal dopants,respectively,on the photocatalytic activity of exfoliated graphitic carbon nitride(g-C_(3)...This study systematically studied the effects of Pr,Fe,and Na as representative rare earth,transition,and alkali metal dopants,respectively,on the photocatalytic activity of exfoliated graphitic carbon nitride(g-C_(3)N_(4)).The doped exfoliated g-C_(3)N_(4)samples were prepared by integrating precursor ion intercalation into the pre-formed g-C_(3)N_(4)with thermal treatment.The as-prepared catalysts were examined for crystal,textural,chemical,optical,and photoelectrochemical properties to explore the correlation between dopants and photocatalytic activity of the resulting composites.The detailed analyses revealed that the Pr-doped g-C_(3)N_(4)exhibited superior photocatalytic activity in degrading methylene blue under visible light,achieving a~96%removal in 40 min.This was not only better than the activity of g-C_(3)N_(4),but also much higher than that of Na-doped g-C_(3)N_(4)or Fe-doped g-C_(3)N_(4).The kinetic rate constant using Pr-doped g-C_(3)N_(4)was 3.2,5.1,and 2.0 times greater than that of the g-C_(3)N_(4),Fe-doped g-C_(3)N_(4),and Na-doped g-C_(3)N_(4),respectively.The enhanced performance was attributed to its inherent characteristics after optimal tuning,including good surface area,improved porosity,enhanced visible light absorption,suitable electronic band structure,increased charge carrier density,promoted charge separation,and reduced charge transfer resistance.In addition,the optimized Pr(0.4)g-C_(3)N_(4)was used to study the photocatalytic removal of methylene blue in detail under conditions with different initial methylene blue concentrations,types of dyes,catalyst dosages,initial solution pH,counter ions,and water matrices.Our results demonstrated the high photocatalytic activity of Pr(0.4)g-C_(3)N_(4)under varying conditions,including in real wastewater media,which were collected from our local municipal wastewater treatment plant.The observed good reusability and stability after five cycles of photocatalytic degradation test further suggested a promising potential of Pr(0.4)g-C_(3)N_(4)for practical application in wastewater treatment.展开更多
文摘This study systematically studied the effects of Pr,Fe,and Na as representative rare earth,transition,and alkali metal dopants,respectively,on the photocatalytic activity of exfoliated graphitic carbon nitride(g-C_(3)N_(4)).The doped exfoliated g-C_(3)N_(4)samples were prepared by integrating precursor ion intercalation into the pre-formed g-C_(3)N_(4)with thermal treatment.The as-prepared catalysts were examined for crystal,textural,chemical,optical,and photoelectrochemical properties to explore the correlation between dopants and photocatalytic activity of the resulting composites.The detailed analyses revealed that the Pr-doped g-C_(3)N_(4)exhibited superior photocatalytic activity in degrading methylene blue under visible light,achieving a~96%removal in 40 min.This was not only better than the activity of g-C_(3)N_(4),but also much higher than that of Na-doped g-C_(3)N_(4)or Fe-doped g-C_(3)N_(4).The kinetic rate constant using Pr-doped g-C_(3)N_(4)was 3.2,5.1,and 2.0 times greater than that of the g-C_(3)N_(4),Fe-doped g-C_(3)N_(4),and Na-doped g-C_(3)N_(4),respectively.The enhanced performance was attributed to its inherent characteristics after optimal tuning,including good surface area,improved porosity,enhanced visible light absorption,suitable electronic band structure,increased charge carrier density,promoted charge separation,and reduced charge transfer resistance.In addition,the optimized Pr(0.4)g-C_(3)N_(4)was used to study the photocatalytic removal of methylene blue in detail under conditions with different initial methylene blue concentrations,types of dyes,catalyst dosages,initial solution pH,counter ions,and water matrices.Our results demonstrated the high photocatalytic activity of Pr(0.4)g-C_(3)N_(4)under varying conditions,including in real wastewater media,which were collected from our local municipal wastewater treatment plant.The observed good reusability and stability after five cycles of photocatalytic degradation test further suggested a promising potential of Pr(0.4)g-C_(3)N_(4)for practical application in wastewater treatment.
