The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount...The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount on degradation of formaldehyde gas were investigated. The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action, e.g,, it could considerably increase decomposing of formaldehyde. The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84--24 mg/m^3 by O3/TiO2flJV process. The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m^3. Furthermore, the kinetics of formaldehyde degradation reaction could be described by Langmuir-Hinshelwood model. The rate constant k of 46.72 mg/（m^3.min） and Langmuir adsorption coefficient K of 0.0268 m^3/mg were obtained.展开更多
Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporo...Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.展开更多
[Objective] The paper aimed to study on the effects of photocatalytic degradation of microcystins MC-RR and MC-LR by UV/Fenton/TiO2 in depth lake water.[Method] With Fenton-TiO2 as photocatalyst,the influences of diff...[Objective] The paper aimed to study on the effects of photocatalytic degradation of microcystins MC-RR and MC-LR by UV/Fenton/TiO2 in depth lake water.[Method] With Fenton-TiO2 as photocatalyst,the influences of different reaction time,initial pH value,H2O2 concentration,Fe2+ concentration,TiO2 dosage,light intensity,initial concentration of microcystin on UV/Fenton/TiO2 heterogeneous photocatalytic degradation of microcystin were investigated,and removal effects of microcystin between heterogeneous photocatalytic degradation and UV photolysis were compared at the same time.[Result] Under the conditions that the initial concentration of H2O2 was 0.1 mmol/L,[H2O2]/[FeSO4] was 15:1,pH value was 4.0,the distance between the reaction solution and UV lamp tube was 1 cm,TiO2 dosage was 0.05 g/L,reaction temperature was (16±2) ℃,the removal rate of MC-RR with concentration of 0.35 mg/L and MC-LR with concentration of 0.29 mg/L could reach 91.5% and 90.2% after 3 minutes reacting.[Conclusion] UV/Fenton/TiO2 photocatalytic oxidation was proved to be effective in degradating microcystins.展开更多
Titanium dioxide (TiO_2) thin films were prepared on microscopes slides by sol-gel and dip-coating processes from specially formulated sols.The results show that there exists anatase and rutile structure of TiO_2 when...Titanium dioxide (TiO_2) thin films were prepared on microscopes slides by sol-gel and dip-coating processes from specially formulated sols.The results show that there exists anatase and rutile structure of TiO_2 when heat treatment temperature is 450℃,and at 800℃,TiO_2 particle size is of below 100 nm and rutile structure is presented.In the range of 360 nm～400 nm the transmittance of TiO_2 sol increases with the increasing of the concentration of Ti(OC_4H_9)_4 in ethanol solution. The transmittance of TiO_2 films with various number of the layer is measured to be 0% below 320 nm,and the three-layer TiO_2 film is of the best UV resistance in the range of 320 nm～400 nm.展开更多
The synergistic effect of H_3PMo_(12)O_(40) or H_3PW_(12)O_(40) polyoxometalate solution(POM) and TiO_2 to catalyze formic acid oxidation was investigated. Under UV irradiation, hole and electron were photogenerated b...The synergistic effect of H_3PMo_(12)O_(40) or H_3PW_(12)O_(40) polyoxometalate solution(POM) and TiO_2 to catalyze formic acid oxidation was investigated. Under UV irradiation, hole and electron were photogenerated by TiO_2. Formic acid was oxided by the photogenerated hole and photogenerated electron was transferred to reduce polyoxometalate. With this design, formic acid can be converted into electricity in the fuel cell and hydrogen can be generated in the electrolysis cell without noble metal catalyst. Unlike other noble metal catalysts applied in the fuel cells and electrolysis cell, POM and TiO_2 are stable and low cost. The maximum output power density of liquid formic acid fuel cell after 12 h UV irradiation is 5.21 mW/cm^2 for phosphmolybdic acid and 22.81 m W/cm^2 for phosphotungstic acid respectively. The applied potential for the hydrogen evolution is as low as 0.8 V for phosphmolybdic acid and 0.6 V for phosphotungstic acid.展开更多
基金Project supported by the Science Project of Harbin City(No. H2001-12)the Youth Foundation of School of Municipal and Environmental Engineering in Harbin Institute of Technology(No. 01306914).
文摘The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount on degradation of formaldehyde gas were investigated. The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action, e.g,, it could considerably increase decomposing of formaldehyde. The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84--24 mg/m^3 by O3/TiO2flJV process. The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m^3. Furthermore, the kinetics of formaldehyde degradation reaction could be described by Langmuir-Hinshelwood model. The rate constant k of 46.72 mg/（m^3.min） and Langmuir adsorption coefficient K of 0.0268 m^3/mg were obtained.
基金the National Natural Science Foundation of China(21501137)the Hubei Natural Science Foundation for financial support(2018CFB680)Support from the Australian Research Council(ARC)through ARC Discovery projects(DP130102699,DP 130102274,DP160102627)
文摘Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.
基金Supported by the Social Development Scientific and Technolgical Project[GKHS-2007-1007]The Special Funds for Top Talents [GSZH-2007-108]The Special Project for Improving Researeh Conditionsof Guizhou [TZJF-2007-15]
文摘[Objective] The paper aimed to study on the effects of photocatalytic degradation of microcystins MC-RR and MC-LR by UV/Fenton/TiO2 in depth lake water.[Method] With Fenton-TiO2 as photocatalyst,the influences of different reaction time,initial pH value,H2O2 concentration,Fe2+ concentration,TiO2 dosage,light intensity,initial concentration of microcystin on UV/Fenton/TiO2 heterogeneous photocatalytic degradation of microcystin were investigated,and removal effects of microcystin between heterogeneous photocatalytic degradation and UV photolysis were compared at the same time.[Result] Under the conditions that the initial concentration of H2O2 was 0.1 mmol/L,[H2O2]/[FeSO4] was 15:1,pH value was 4.0,the distance between the reaction solution and UV lamp tube was 1 cm,TiO2 dosage was 0.05 g/L,reaction temperature was (16±2) ℃,the removal rate of MC-RR with concentration of 0.35 mg/L and MC-LR with concentration of 0.29 mg/L could reach 91.5% and 90.2% after 3 minutes reacting.[Conclusion] UV/Fenton/TiO2 photocatalytic oxidation was proved to be effective in degradating microcystins.
文摘Titanium dioxide (TiO_2) thin films were prepared on microscopes slides by sol-gel and dip-coating processes from specially formulated sols.The results show that there exists anatase and rutile structure of TiO_2 when heat treatment temperature is 450℃,and at 800℃,TiO_2 particle size is of below 100 nm and rutile structure is presented.In the range of 360 nm～400 nm the transmittance of TiO_2 sol increases with the increasing of the concentration of Ti(OC_4H_9)_4 in ethanol solution. The transmittance of TiO_2 films with various number of the layer is measured to be 0% below 320 nm,and the three-layer TiO_2 film is of the best UV resistance in the range of 320 nm～400 nm.
文摘The synergistic effect of H_3PMo_(12)O_(40) or H_3PW_(12)O_(40) polyoxometalate solution(POM) and TiO_2 to catalyze formic acid oxidation was investigated. Under UV irradiation, hole and electron were photogenerated by TiO_2. Formic acid was oxided by the photogenerated hole and photogenerated electron was transferred to reduce polyoxometalate. With this design, formic acid can be converted into electricity in the fuel cell and hydrogen can be generated in the electrolysis cell without noble metal catalyst. Unlike other noble metal catalysts applied in the fuel cells and electrolysis cell, POM and TiO_2 are stable and low cost. The maximum output power density of liquid formic acid fuel cell after 12 h UV irradiation is 5.21 mW/cm^2 for phosphmolybdic acid and 22.81 m W/cm^2 for phosphotungstic acid respectively. The applied potential for the hydrogen evolution is as low as 0.8 V for phosphmolybdic acid and 0.6 V for phosphotungstic acid.
