The construction of efficient photocatalysts has received much attention in wastewater treatment.In this study,Nb-doped NaTaO_(3) was prepared with different doping ratio by a facile hydrothermal method.The prepared c...The construction of efficient photocatalysts has received much attention in wastewater treatment.In this study,Nb-doped NaTaO_(3) was prepared with different doping ratio by a facile hydrothermal method.The prepared catalysts were analyzed by X-ray diffraction,scanning electron microscopy,Brunauer-EmmettTeller(BET)theory,ultraviolet–visible diffuse reflectance spectroscopy.Then the synthesized catalysts were employed to degrade a model pollutant,methylene blue(MB),under a 250 W mercury lamp.The characterization tests confirm that Nb was successfully doped into the crystal structure of NaTaO_(3) and the modified NaNb_(x)Ta_(1)·xO_(3)(x is the doping ratio;x=0.25,0.5,0.75)samples were formed,which were in regular cubic shapes just like pure NaTaO_(3).The synthesized NaNb_(x)Ta_(1)·xO_(3)(x=0.25,0.5,0.75)had improved specific surface area and narrowed band gaps compared with pure NaTaO_(3).In photocatalytic degradation experiments,NaNb0.75Ta0.25O_(3) presented the best photocatalytic activity ascribed to the narrow band gap and the high surface area,degradating 95.7%of MB after 180 min of reaction,which was even twice the ability of pure NaTaO_(3).Besides,the effects of possible inorganic anions and cations in wastewater on photocatalytic degradation were investigated.Electron spin resonance(ESR)tests and capture experiments were also conducted and a possible photocatalytic mechanism was proposed.This work provides a direction for constructing superior NaTaO_(3)-based photocatalysts to be widely utilized in environmental protection.展开更多
Photothermal CO_(2)reduction with H2O,integrating advantages of photocatalysis driven H2O splitting and thermal catalysis promoted CO_(2)reduction,has drawn sharply increasing attention in artificial synthesis of sola...Photothermal CO_(2)reduction with H2O,integrating advantages of photocatalysis driven H2O splitting and thermal catalysis promoted CO_(2)reduction,has drawn sharply increasing attention in artificial synthesis of solar fuels.The photothermal effect of metal nanoparticles facilities CO_(2)hydrogenation and activation of lattice oxygen in oxide photocatalyst promotes H2O oxidation,which is essentially considered for highly efficient photothermal catalysis.However,the large thermal conductivity of most metal nanoparticles induces inevitable heat dissipation,restricting the increase of catalyst temperature.In this work,to minimize the heat dissipation,we employ bismuth nanoparticles as photothermal unit,which is of the lowest thermal conductivity in the metal family.Meanwhile,we adopt bismuth doped NaTaO_(3)as photocatalytic unit because of the bismuth doping induced activation of lattice oxygen.The bismuth nanoparticles are assembled with bismuth doped NaTaO_(3)through one-step tunable transformation from Bi4TaO8Cl.Benefiting from the photothermal effect,thermal insulation caused by bismuth metal,and lattice oxygen activation by bismuth doping,the NaTaO_(3):Bi hybrid exhibits high photothermal catalytic performance.The yield of CO over NaTaO_(3):Bi hybrid at 413 K via photothermal catalysis is 141 times higher than that room temperature photocatalysis.Further,ultraviolet(UV)light irradiation leads to 89.2%selectivity of CO and visible light irradiation leads to 97.5%selectivity of CH4.This work may broaden the photocatalytic application of ABO_(3)perovskite and provides a novel strategy for the development of photothermal catalysts for artificial photosynthesis.展开更多
Removing large concentrations of organic pollutants from water efficiently and quickly under visible light is essential to developing photocatalytic technology and improving solar energy efficiency.This study used a s...Removing large concentrations of organic pollutants from water efficiently and quickly under visible light is essential to developing photocatalytic technology and improving solar energy efficiency.This study used a simple hydrothermal method to prepare a non-metallic,S-doped NaTaO_(3)(S-NTO) photocatalyst,which was then loaded onto biochar (BC) to form a S-NTO/BC composite photocatalyst.After uniform loading onto BC,the S-NTO particles transformed from cubic to spherical.The photogenerated electron-hole pair recombination probability of the composite photocatalyst was significantly lower than those of the NTO particles.The light absorption range of the catalyst was effectively widened from 310 nm UV region to visible region.In addition,a dual-effect catalytic system was constructed by introducing peroxymonosulfate (PMS) into the environment of the pollution to be degraded.The Rhodamine B,Methyl Orange,Acid Orange 7,tetracycline,and ciprofloxacin degradation efficiency at 40 mg/L reached 99.6%,99.2%,84.5%,67.1%,and 70.7%,respectively,after irradiation by a 40 W lamps for 90 min.The high-efficiency visible-light catalytic activity of the dual-effect catalytic system was attributed to doping with non-metallic sulfur and loading of catalysts onto BC.The development of this dual-effect catalytic system provides new ideas for quickly and efficiently solving the problem of high-concentration organic pollution in aqueous environments,rationally and fully utilizing solar energy,and expanding the application of photocatalytic technology to practice.展开更多
基金This work was supported by the Innovative Research Groups of the National Natural Science Foundation of China(51621005).
文摘The construction of efficient photocatalysts has received much attention in wastewater treatment.In this study,Nb-doped NaTaO_(3) was prepared with different doping ratio by a facile hydrothermal method.The prepared catalysts were analyzed by X-ray diffraction,scanning electron microscopy,Brunauer-EmmettTeller(BET)theory,ultraviolet–visible diffuse reflectance spectroscopy.Then the synthesized catalysts were employed to degrade a model pollutant,methylene blue(MB),under a 250 W mercury lamp.The characterization tests confirm that Nb was successfully doped into the crystal structure of NaTaO_(3) and the modified NaNb_(x)Ta_(1)·xO_(3)(x is the doping ratio;x=0.25,0.5,0.75)samples were formed,which were in regular cubic shapes just like pure NaTaO_(3).The synthesized NaNb_(x)Ta_(1)·xO_(3)(x=0.25,0.5,0.75)had improved specific surface area and narrowed band gaps compared with pure NaTaO_(3).In photocatalytic degradation experiments,NaNb0.75Ta0.25O_(3) presented the best photocatalytic activity ascribed to the narrow band gap and the high surface area,degradating 95.7%of MB after 180 min of reaction,which was even twice the ability of pure NaTaO_(3).Besides,the effects of possible inorganic anions and cations in wastewater on photocatalytic degradation were investigated.Electron spin resonance(ESR)tests and capture experiments were also conducted and a possible photocatalytic mechanism was proposed.This work provides a direction for constructing superior NaTaO_(3)-based photocatalysts to be widely utilized in environmental protection.
基金supported by the Natural Science Foundation of China(Nos.91833303,52273236,and 51872044)the 111 Project(No.B13013)Jilin Province Science and Technology Development Project(No.20220201073GX).
文摘Photothermal CO_(2)reduction with H2O,integrating advantages of photocatalysis driven H2O splitting and thermal catalysis promoted CO_(2)reduction,has drawn sharply increasing attention in artificial synthesis of solar fuels.The photothermal effect of metal nanoparticles facilities CO_(2)hydrogenation and activation of lattice oxygen in oxide photocatalyst promotes H2O oxidation,which is essentially considered for highly efficient photothermal catalysis.However,the large thermal conductivity of most metal nanoparticles induces inevitable heat dissipation,restricting the increase of catalyst temperature.In this work,to minimize the heat dissipation,we employ bismuth nanoparticles as photothermal unit,which is of the lowest thermal conductivity in the metal family.Meanwhile,we adopt bismuth doped NaTaO_(3)as photocatalytic unit because of the bismuth doping induced activation of lattice oxygen.The bismuth nanoparticles are assembled with bismuth doped NaTaO_(3)through one-step tunable transformation from Bi4TaO8Cl.Benefiting from the photothermal effect,thermal insulation caused by bismuth metal,and lattice oxygen activation by bismuth doping,the NaTaO_(3):Bi hybrid exhibits high photothermal catalytic performance.The yield of CO over NaTaO_(3):Bi hybrid at 413 K via photothermal catalysis is 141 times higher than that room temperature photocatalysis.Further,ultraviolet(UV)light irradiation leads to 89.2%selectivity of CO and visible light irradiation leads to 97.5%selectivity of CH4.This work may broaden the photocatalytic application of ABO_(3)perovskite and provides a novel strategy for the development of photothermal catalysts for artificial photosynthesis.
基金financially supported by the Science and Technology Major Project on Lakes of Inner Mongolia (No.ZDZX2018054)the National Natural Science Foundation of China for Less Developed Regions (No.51868054)+1 种基金Innovation Guide Project of Inner Mongolia Autonomous Region (No.KCBJ2018005)Inner Mongolia University special funds for postgraduate innovation and entrepreneurship (No.11200-121024)。
文摘Removing large concentrations of organic pollutants from water efficiently and quickly under visible light is essential to developing photocatalytic technology and improving solar energy efficiency.This study used a simple hydrothermal method to prepare a non-metallic,S-doped NaTaO_(3)(S-NTO) photocatalyst,which was then loaded onto biochar (BC) to form a S-NTO/BC composite photocatalyst.After uniform loading onto BC,the S-NTO particles transformed from cubic to spherical.The photogenerated electron-hole pair recombination probability of the composite photocatalyst was significantly lower than those of the NTO particles.The light absorption range of the catalyst was effectively widened from 310 nm UV region to visible region.In addition,a dual-effect catalytic system was constructed by introducing peroxymonosulfate (PMS) into the environment of the pollution to be degraded.The Rhodamine B,Methyl Orange,Acid Orange 7,tetracycline,and ciprofloxacin degradation efficiency at 40 mg/L reached 99.6%,99.2%,84.5%,67.1%,and 70.7%,respectively,after irradiation by a 40 W lamps for 90 min.The high-efficiency visible-light catalytic activity of the dual-effect catalytic system was attributed to doping with non-metallic sulfur and loading of catalysts onto BC.The development of this dual-effect catalytic system provides new ideas for quickly and efficiently solving the problem of high-concentration organic pollution in aqueous environments,rationally and fully utilizing solar energy,and expanding the application of photocatalytic technology to practice.
