In this work. phenol and oxalic acid （OA） degradation in an ozone and photocatalysis integrated process was intensively conducted with Fe3 ＋/TiO2 catalyst. The ferrioxalate complex formed between Fe3＋ and oxalate ...In this work. phenol and oxalic acid （OA） degradation in an ozone and photocatalysis integrated process was intensively conducted with Fe3 ＋/TiO2 catalyst. The ferrioxalate complex formed between Fe3＋ and oxalate accelerated the removal of OA in the ozonation, photolysis and photocatalytic ozonation process, for its high reactivity with ozone and UV. Phenol was degraded in ozonation and photolysis with limited TOC removal rates, but much higher TOC removal was achieved in photocatalytic ozonation due to the generation of-OH. The sequence of UV light and ozone in the sequential process also influences the TOC removal, and ozone is very powerful to oxidize intermediates catechol and hydroquinone to maleic acid. Fenton or photo-Fenton reactions only played a small part in Fe3＋/TiO2 catalyzed processes, because Fe＋ was greatly reduced but not regenerated in many cases. The synergetic effect was found to be highly related with the property of the target pollutants. Fe3 ＋/TiO2 catalyzed system showed the highest ability to destroy organics, but the TiO2 catalyzed system showed little higher synergy.展开更多
Although TiO2-based nanostructures with unique chemical and physical properties exhibit great promise in water treatment and energy conversion/storage,there still exist some limitations.In order to further improve the...Although TiO2-based nanostructures with unique chemical and physical properties exhibit great promise in water treatment and energy conversion/storage,there still exist some limitations.In order to further improve the photochemical properties,one-dimension TiO2 nanoarrays on the substrate are primarily combined with graphene by various preparation technologies.The composite coating has exhibited extraordinary photocatalytic abilities in the degradation of organic pollutants into less toxic compounds,antimicrobial activity and adsorption capacity in water treatment.Especially,it is easy to recycle after photocatalytic reaction.Additionally,TiO2 nanoarrays/graphene on the substrate(especially flexible substrate)could provide potential opportunities for flexible-device fabrication with excellent photovoltaic conversion efficiency and electrochemical performance in energy conversion/storage devices.As far as we know,the relevant reviews have rarely been reported.Here,we present a comprehensive review on the preparation of TiO2 nanoarrays or TiO2 nanoarrays/graphene,and their application and mechanism in water treatment and energy conversion/storage.展开更多
In this work, we have shown that mining waste derived Fe^3＋can be used to enhance the photocatalytic activity of TiO2. This will allow us to harness a waste product from the mines, and utilize it to enhance TiO2 phot...In this work, we have shown that mining waste derived Fe^3＋can be used to enhance the photocatalytic activity of TiO2. This will allow us to harness a waste product from the mines, and utilize it to enhance TiO2 photocatalytic waste water treatment efficiency. An organic linker mediated route was utilized to create a composite of TiO2 and biogenic jarosite. Evidence of Fe／O／Ti bonding in the TiO2/jarosite composite was apparent from the FTIR, EFTEM, EELS and ELNEFS analysis. The as prepared material showed enhanced photocatalytic activity compared to pristine TiO2, biogenic jarosite and mechanically mixed sample of jarosite and TiO2 under both simulated and natural solar irradiation. The prepared material can reduce the electrical energy consumption by 4 times compared to pristine P25 for degradation of organic pollutant in water. The material also showed good recyclability. Results obtained from sedimentation experiments showed that the larger sized jarosite material provided the surface to TiO2 nanoparticles, which increases the settling rate of the materials. This allowed simple and efficient recovery of the catalyst from the reaction system after completion of photocatalysis. Enhanced photocatalytic activity of the composite material was due to effective charge transfer between TiO2 and jarosite derived Fe^3＋as was shown from the EELS and ELNEFS. Generation of OHU was supported by photoluminesence（PL） experiments.展开更多
基金Supported by the Natural Science Foundation of Beijing City(8172043)the National Science Fund for Distinguished Young Scholars(51425405)National Natural Science Foundation of China(51378487)
文摘In this work. phenol and oxalic acid （OA） degradation in an ozone and photocatalysis integrated process was intensively conducted with Fe3 ＋/TiO2 catalyst. The ferrioxalate complex formed between Fe3＋ and oxalate accelerated the removal of OA in the ozonation, photolysis and photocatalytic ozonation process, for its high reactivity with ozone and UV. Phenol was degraded in ozonation and photolysis with limited TOC removal rates, but much higher TOC removal was achieved in photocatalytic ozonation due to the generation of-OH. The sequence of UV light and ozone in the sequential process also influences the TOC removal, and ozone is very powerful to oxidize intermediates catechol and hydroquinone to maleic acid. Fenton or photo-Fenton reactions only played a small part in Fe3＋/TiO2 catalyzed processes, because Fe＋ was greatly reduced but not regenerated in many cases. The synergetic effect was found to be highly related with the property of the target pollutants. Fe3 ＋/TiO2 catalyzed system showed the highest ability to destroy organics, but the TiO2 catalyzed system showed little higher synergy.
基金supported by the National Natural Science Foundation for Distinguished Young Scholars (51425204)
文摘Although TiO2-based nanostructures with unique chemical and physical properties exhibit great promise in water treatment and energy conversion/storage,there still exist some limitations.In order to further improve the photochemical properties,one-dimension TiO2 nanoarrays on the substrate are primarily combined with graphene by various preparation technologies.The composite coating has exhibited extraordinary photocatalytic abilities in the degradation of organic pollutants into less toxic compounds,antimicrobial activity and adsorption capacity in water treatment.Especially,it is easy to recycle after photocatalytic reaction.Additionally,TiO2 nanoarrays/graphene on the substrate(especially flexible substrate)could provide potential opportunities for flexible-device fabrication with excellent photovoltaic conversion efficiency and electrochemical performance in energy conversion/storage devices.As far as we know,the relevant reviews have rarely been reported.Here,we present a comprehensive review on the preparation of TiO2 nanoarrays or TiO2 nanoarrays/graphene,and their application and mechanism in water treatment and energy conversion/storage.
基金supported by the National Research Foundation(No.88220,and 91510)
文摘In this work, we have shown that mining waste derived Fe^3＋can be used to enhance the photocatalytic activity of TiO2. This will allow us to harness a waste product from the mines, and utilize it to enhance TiO2 photocatalytic waste water treatment efficiency. An organic linker mediated route was utilized to create a composite of TiO2 and biogenic jarosite. Evidence of Fe／O／Ti bonding in the TiO2/jarosite composite was apparent from the FTIR, EFTEM, EELS and ELNEFS analysis. The as prepared material showed enhanced photocatalytic activity compared to pristine TiO2, biogenic jarosite and mechanically mixed sample of jarosite and TiO2 under both simulated and natural solar irradiation. The prepared material can reduce the electrical energy consumption by 4 times compared to pristine P25 for degradation of organic pollutant in water. The material also showed good recyclability. Results obtained from sedimentation experiments showed that the larger sized jarosite material provided the surface to TiO2 nanoparticles, which increases the settling rate of the materials. This allowed simple and efficient recovery of the catalyst from the reaction system after completion of photocatalysis. Enhanced photocatalytic activity of the composite material was due to effective charge transfer between TiO2 and jarosite derived Fe^3＋as was shown from the EELS and ELNEFS. Generation of OHU was supported by photoluminesence（PL） experiments.
