Fe^3＋ -doped nanometer TiO2 photocatalysts were prepared by sol-gel technique. TiO2 powders with different Fe^3＋ / Ti^4 ＋ molar ratios ranging from 0. 05% to 25% were synthesized by calcinating the gels in the temp...Fe^3＋ -doped nanometer TiO2 photocatalysts were prepared by sol-gel technique. TiO2 powders with different Fe^3＋ / Ti^4 ＋ molar ratios ranging from 0. 05% to 25% were synthesized by calcinating the gels in the temperature range of 200-600 ℃ . The effects of the content of iron ions and calcination temperature on the physical properties of the powders and their photocatalytic activities were examined by the photodecorapositon of methyl orange in sunlight. The results show that Fe dopant can decrease the temperature of nanatase-ratile transformation. The ideal photocatalytic property was achieved when the sample with an Fe^3＋ / Ti^4＋ ratio of 20 at% was calcined at about 300 ℃ for an hour, which is superior to that of commercial Degussa P-25. The optimum microstructure of the Fe-doped TiO2 for a high photocatalytic activity in sunlight is consisted of nanatase and ratile.展开更多
The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water.To achieve efficient sedimentation of coal slurry water,this paper introduces a novel approach that re...The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water.To achieve efficient sedimentation of coal slurry water,this paper introduces a novel approach that regulates the hydrophobicity of defective active sites in clay minerals.Fe^(3+)-doped kaolinite(Fe^(3+)-Kao)was synthesized by hydrothermal methods.Subsequently,tests were conducted on the adsorption capacity,surface wettability,and agglomeration sedimentation of alkyl amine/ammonium salts(AAS)on Fe^(3+)-Kao surfaces.Fe^(3+)doping significantly enhances AAS adsorption and alters surface properties from hydrophilic to hydrophobic,promoting kaolinite particle aggregation and sedimentation,thereby improving coal slurry water treatment efficiency.Molecular dynamics(MD)simulations were performed to analyze the statistical adsorption behavior of AAS on Fe^(3+)-Kao surfaces.The simulation results indicate that the mechanism by which Fe^(3+)doping influences the hydrophobic regulation of kaolinite surfaces is due to the enhanced interfacial interactions between the kaolinite surface and AAS,where the interfacial effects are more pronounced on surfaces closer to the dopant sites.The findings of this research offer valuable insights for future studies on other types of lattice defects in clay minerals,as well as for the development of more efficient treatment chemicals for coal slurry water.展开更多
A novel Ni doped carbon quantum dots(Ni-CQDs)fluorescence probe was synthesized by facile electrolysis of monoatomic Ni dispersed porous carbon(Ni–N–C).The obtained Ni-CQDs showed a high quantum yield of 6.3%with th...A novel Ni doped carbon quantum dots(Ni-CQDs)fluorescence probe was synthesized by facile electrolysis of monoatomic Ni dispersed porous carbon(Ni–N–C).The obtained Ni-CQDs showed a high quantum yield of 6.3%with the strongest excitation and emission peaks of 360 nm and 460 nm,and maintained over 90%of the maximum fluorescence intensity in a wide p H range of 3–12.The metal ions detectability of Ni-CQDs was enhanced by Ni doping and functional groups modification,and the rapid and selective detection of Fe^(3+)and Cu^(2+)ions was achieved with Ni-CQDs through dynamic and static quenching mechanism,respectively.On one hand,the energy band gap of Ni-CQDs was regulated by Ni doping,so that excited electrons in Ni-CQDs were able to transfer to Fe^(3+)easily.On the other hand,the abundant functional groups promoted the generation of static quenching complexation between Cu^(2+)and Ni-CQDs.In metal ions detection,the linear quantitation range of Fe^(3+)and Cu^(2+)were 100–1000μM(R^(2)=0.9955)and 300–900μM(R^(2)=0.9978),respectively.The limits of detection(LOD)were calculated as 10.17 and 7.88μM,respectively.Moreover,the fluorescence quenched by Cu^(2+)could be recovered by EDTA2-due to the destruction of the static quenching complexation.In this way,NiCQDs showed the ability to identify the two metal ions to a certain degree under the condition of Fe^(3+)and Cu^(2+)coexistent.This work paves the way of facile multiple metal ion detection with high sensitivity.展开更多
基金Founded by the Science and Technology Foundation of AnhuiProvince (No.010301E2)
文摘Fe^3＋ -doped nanometer TiO2 photocatalysts were prepared by sol-gel technique. TiO2 powders with different Fe^3＋ / Ti^4 ＋ molar ratios ranging from 0. 05% to 25% were synthesized by calcinating the gels in the temperature range of 200-600 ℃ . The effects of the content of iron ions and calcination temperature on the physical properties of the powders and their photocatalytic activities were examined by the photodecorapositon of methyl orange in sunlight. The results show that Fe dopant can decrease the temperature of nanatase-ratile transformation. The ideal photocatalytic property was achieved when the sample with an Fe^3＋ / Ti^4＋ ratio of 20 at% was calcined at about 300 ℃ for an hour, which is superior to that of commercial Degussa P-25. The optimum microstructure of the Fe-doped TiO2 for a high photocatalytic activity in sunlight is consisted of nanatase and ratile.
基金supported by the National key research and development Program of China(No.2023YFE0100600)the National Natural Science Foundation of China(Nos.52174233 and 52474282)the Natural Science Research Project of Anhui Educational Committee(No.2022AH030083)。
文摘The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water.To achieve efficient sedimentation of coal slurry water,this paper introduces a novel approach that regulates the hydrophobicity of defective active sites in clay minerals.Fe^(3+)-doped kaolinite(Fe^(3+)-Kao)was synthesized by hydrothermal methods.Subsequently,tests were conducted on the adsorption capacity,surface wettability,and agglomeration sedimentation of alkyl amine/ammonium salts(AAS)on Fe^(3+)-Kao surfaces.Fe^(3+)doping significantly enhances AAS adsorption and alters surface properties from hydrophilic to hydrophobic,promoting kaolinite particle aggregation and sedimentation,thereby improving coal slurry water treatment efficiency.Molecular dynamics(MD)simulations were performed to analyze the statistical adsorption behavior of AAS on Fe^(3+)-Kao surfaces.The simulation results indicate that the mechanism by which Fe^(3+)doping influences the hydrophobic regulation of kaolinite surfaces is due to the enhanced interfacial interactions between the kaolinite surface and AAS,where the interfacial effects are more pronounced on surfaces closer to the dopant sites.The findings of this research offer valuable insights for future studies on other types of lattice defects in clay minerals,as well as for the development of more efficient treatment chemicals for coal slurry water.
基金the National Natural Science Foundation of China(Nos.21776302 and 21776308)the Science Foundation of China University of Petroleum,Beijing(No.2462020YXZZ033)。
文摘A novel Ni doped carbon quantum dots(Ni-CQDs)fluorescence probe was synthesized by facile electrolysis of monoatomic Ni dispersed porous carbon(Ni–N–C).The obtained Ni-CQDs showed a high quantum yield of 6.3%with the strongest excitation and emission peaks of 360 nm and 460 nm,and maintained over 90%of the maximum fluorescence intensity in a wide p H range of 3–12.The metal ions detectability of Ni-CQDs was enhanced by Ni doping and functional groups modification,and the rapid and selective detection of Fe^(3+)and Cu^(2+)ions was achieved with Ni-CQDs through dynamic and static quenching mechanism,respectively.On one hand,the energy band gap of Ni-CQDs was regulated by Ni doping,so that excited electrons in Ni-CQDs were able to transfer to Fe^(3+)easily.On the other hand,the abundant functional groups promoted the generation of static quenching complexation between Cu^(2+)and Ni-CQDs.In metal ions detection,the linear quantitation range of Fe^(3+)and Cu^(2+)were 100–1000μM(R^(2)=0.9955)and 300–900μM(R^(2)=0.9978),respectively.The limits of detection(LOD)were calculated as 10.17 and 7.88μM,respectively.Moreover,the fluorescence quenched by Cu^(2+)could be recovered by EDTA2-due to the destruction of the static quenching complexation.In this way,NiCQDs showed the ability to identify the two metal ions to a certain degree under the condition of Fe^(3+)and Cu^(2+)coexistent.This work paves the way of facile multiple metal ion detection with high sensitivity.
