A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment...A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment.The physiochemical properties of composites were characterized thoroughly.It has found that heating temperature and N-doping through NH_3-ambiance pyrolysis significantly influence the visible-light sensitivity and bandgap energy of composites.The catalytic activities of composites were measured by degradation of Methylene Blue(MB)in the presence or absence of H_2O_2 and visible-light irradiation.Our best catalyst(N–TiO_2–Fe_3O_4-biochar)exhibits rapid and high MB removal competency(99.99%)via synergism of adsorption,photodegradation,and Fenton-like reaction.Continuous production of O_2U^-and UOH radicles performs MB degradation and mineralization,confirmed by scavenging experiments and degradation product analysis.The local trap state Ti^(3+),Fe_3O_4,and N-carbon of the catalyst acted as active sites.It has suggested that the Ti^(3+)and N-doped dense carbon layer improve charge separation and shuttle that prolonged photo-Fenton like reaction.Moreover,the catalyst is highly stable,collectible,and recyclable up to 5 cycles with high MB degradation efficiency.This work provides a new insight into the synthesis of highly visible-light sensitized biocharsupported photocatalyst through NH_3-ambiance pyrolysis of NPs-laden biomass.展开更多
The yellowish nitrogen and iron co-doped nanocrystalline titanium dioxide((Fe,N)co-doped TiO2)powders have been prepared by hydrothermal method using TiOSO4 and CO(NH2)2 as starting materials.The grain size of the syn...The yellowish nitrogen and iron co-doped nanocrystalline titanium dioxide((Fe,N)co-doped TiO2)powders have been prepared by hydrothermal method using TiOSO4 and CO(NH2)2 as starting materials.The grain size of the synthesized powders was estimated as 11 nm by Scherrer's method.The UV-Vis diffuse reflectance spectra indicated that the light absorption edge of the powders was red-shifted up to 605 nm.And the doped TiO2 powders exhibited good photocatalytic activities during the photo-degradation of coking wastewater under sunshine irradiation.The biotreatability of the coking wasterwater after photocatalytic degradation was improved greatly and it is more suitable to be further treated by biochemical method.展开更多
In this paper,a comparative study on the photocatalytic degradation of the Rhodamine B(Rh B)dye as a model compound using N–Fe codoped Ti O2 nanorods under UV and visible-light(λ≥420 nm)irradiations has been perfor...In this paper,a comparative study on the photocatalytic degradation of the Rhodamine B(Rh B)dye as a model compound using N–Fe codoped Ti O2 nanorods under UV and visible-light(λ≥420 nm)irradiations has been performed.Ti O2 photocatalysts were fabricated as aligned nanorod arrays by liquid-phase deposition process,annealed at different temperatures from 400 to 800℃.The effects of annealing temperature on the phase structure,crystallinity,BET surface area,and resulting photocatalytic activity of N–Fe codoped Ti O2 nanorods were also investigated.The degradation studies confirmed that the nanorods annealed at 600℃composed of both anatase(79%)and rutile phases(21%)and offered the highest activity and stability among the series of nanorods,as it degraded 94.8%and 87.2%Rh B in 120 min irradiation under UV and visible-light,respectively.Above 600℃,the photocatalytic performance of nanorods decreased owning to a phase change,decreased surface area and bandgap,and growth of Ti O2 crystallites induced by the annealing temperature.It is hoped that this work could provide precious information on the design of 1 D catalyst materials with more superior photodegradation properties especially under visible-light for the further industrial applications.展开更多
基金supported by the National Basic Research Program of China (973 Program, 2014CB238903)the National Natural Science Foundation of China (Nos. 41672144, 41173032, and 41373110)
文摘A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment.The physiochemical properties of composites were characterized thoroughly.It has found that heating temperature and N-doping through NH_3-ambiance pyrolysis significantly influence the visible-light sensitivity and bandgap energy of composites.The catalytic activities of composites were measured by degradation of Methylene Blue(MB)in the presence or absence of H_2O_2 and visible-light irradiation.Our best catalyst(N–TiO_2–Fe_3O_4-biochar)exhibits rapid and high MB removal competency(99.99%)via synergism of adsorption,photodegradation,and Fenton-like reaction.Continuous production of O_2U^-and UOH radicles performs MB degradation and mineralization,confirmed by scavenging experiments and degradation product analysis.The local trap state Ti^(3+),Fe_3O_4,and N-carbon of the catalyst acted as active sites.It has suggested that the Ti^(3+)and N-doped dense carbon layer improve charge separation and shuttle that prolonged photo-Fenton like reaction.Moreover,the catalyst is highly stable,collectible,and recyclable up to 5 cycles with high MB degradation efficiency.This work provides a new insight into the synthesis of highly visible-light sensitized biocharsupported photocatalyst through NH_3-ambiance pyrolysis of NPs-laden biomass.
基金support by the National Natural Science Foundation of China(Grant No.50772014)the Program for New Century Excellent Talents in Universities(Grant No.NCET-07-0064)
文摘The yellowish nitrogen and iron co-doped nanocrystalline titanium dioxide((Fe,N)co-doped TiO2)powders have been prepared by hydrothermal method using TiOSO4 and CO(NH2)2 as starting materials.The grain size of the synthesized powders was estimated as 11 nm by Scherrer's method.The UV-Vis diffuse reflectance spectra indicated that the light absorption edge of the powders was red-shifted up to 605 nm.And the doped TiO2 powders exhibited good photocatalytic activities during the photo-degradation of coking wastewater under sunshine irradiation.The biotreatability of the coking wasterwater after photocatalytic degradation was improved greatly and it is more suitable to be further treated by biochemical method.
文摘In this paper,a comparative study on the photocatalytic degradation of the Rhodamine B(Rh B)dye as a model compound using N–Fe codoped Ti O2 nanorods under UV and visible-light(λ≥420 nm)irradiations has been performed.Ti O2 photocatalysts were fabricated as aligned nanorod arrays by liquid-phase deposition process,annealed at different temperatures from 400 to 800℃.The effects of annealing temperature on the phase structure,crystallinity,BET surface area,and resulting photocatalytic activity of N–Fe codoped Ti O2 nanorods were also investigated.The degradation studies confirmed that the nanorods annealed at 600℃composed of both anatase(79%)and rutile phases(21%)and offered the highest activity and stability among the series of nanorods,as it degraded 94.8%and 87.2%Rh B in 120 min irradiation under UV and visible-light,respectively.Above 600℃,the photocatalytic performance of nanorods decreased owning to a phase change,decreased surface area and bandgap,and growth of Ti O2 crystallites induced by the annealing temperature.It is hoped that this work could provide precious information on the design of 1 D catalyst materials with more superior photodegradation properties especially under visible-light for the further industrial applications.
