A BiOCl-Bi12O17Cl2 nanocomposite with a high visible-light response and a low photoinduced electron-hole pair recombination rate was successfully synthesized using an ultrasonic-hydrothermal method.The texture,structu...A BiOCl-Bi12O17Cl2 nanocomposite with a high visible-light response and a low photoinduced electron-hole pair recombination rate was successfully synthesized using an ultrasonic-hydrothermal method.The texture,structure,optical,and photocatalytic properties of the composite were characterized.The results showed that the composite had a sheet flower-like structure with a large specific surface area.Ultraviolet-visible diffuse reflection spectra and photoluminescence spectra showed that the composite had an excellent visible-light response and a low recombination rate of photoinduced electron hole pairs.The photocatalytic property of the composite was evaluated by the removal efficiency of rhodamine B and ciprofloxacin under visible-light illumination.The composite’s reaction rate constant of removing rhodamine B(/ciprofloxacin)was approximately 8.14(/4.94),42.63(/11.91)and 64.66(/36.07)times that of Bi12O17Cl2,P25,and BiOCl,respectively.Furthermore,the composite showed a wide applicable pH range and excellent reusability.Mechanism analysis showed that photogenerated holes played a dominant role and·O2–also contributed to photocatalytic degradation.In summary,this study presents a high-efficiency photocatalyst for wastewater treatment.展开更多
This study aimed to explore a new degradation method-photocatalysis technology to polish membrane bioreactor(MBR) effluent, using 2,6-di-tert-butylphenol(2,6-DTBP) as a model soluble microbial product(SMP).2,6-DTBP is...This study aimed to explore a new degradation method-photocatalysis technology to polish membrane bioreactor(MBR) effluent, using 2,6-di-tert-butylphenol(2,6-DTBP) as a model soluble microbial product(SMP).2,6-DTBP is one of the predominant SMPs in MBR effluent, which is refractory and difficult to biodegrade.This study developed a novel carboxylated graphene oxide/titanium dioxide/silver(GO-COOH/TiO2/Ag) nanocomposite to photodegrade 2,6-DTBP.GO-COOH/TiO2/Ag was successfully synthesized, using L-cysteine as the linker bonding TiO2/Ag to GO-COOH.The structural, morphological and optical properties of the GO-COOH/TiO2/Ag nanocomposite were characterized using various techniques.Owing to synergistic effects, the GO-COOH/TiO2/Ag nanocomposite exhibited enhanced photocatalytic degradation performance under solar light irradiation when compared to TiO2, Ag and GO-COOH.To remove 25 mg/L 2,6-DTBP, the reaction time for GOCOOH/TiO2/Ag was only 30 min, faster than the 90 min required for pure TiO2 or Ag.In addition, the 200 mg/L GO-COOH/TiO2/Ag nanocomposite aqueous solution showed the best performance under solar light, with 99% removal of 2,6-DTBP.This enhanced capability is likely due to the surface plasmon resonance(SPR) effect contributed by Ag nanoparticles(NPs) doped onto the TiO2.In addition, GO-COOH had a high effective surface area, which assisted in degrading the 2,6-DTBP through improved adsorption.The stability study showed that the photocatalytic activity of the GO-COOH/TiO2/Ag was stable enough for recycling multiple times.The effective degradation performance and excellent stability demonstrates that the GO-COOH/TiO2/Ag nanocomposite can be a promising photocatalyst in the field of effluent SMP photodegradation, which solves the problem of the difficult biodegradation of highly toxic 2,6-DTBP.展开更多
In this work, Bi2Ti2O7/TiO2 composites were synthesized and studied as potential visible-light-activated photocatalysts in the reduction of aqueous Cr（VI）. Bi2Ti2O7/TiO2 composites with tunable compositions were syn...In this work, Bi2Ti2O7/TiO2 composites were synthesized and studied as potential visible-light-activated photocatalysts in the reduction of aqueous Cr（VI）. Bi2Ti2O7/TiO2 composites with tunable compositions were synthesized via a solvothermal-calcination two-step method, simply by changing the molar ratios of Bi（NO3）3·5H2O to tetrabutyl titanate in the reactants. The compositions, structures and optical properties of the as-synthesized Bi2Ti2O7/TiO2 composites were characterized by X-ray diffraction, field emission scanning electron microscopy and UV–vis diffuse reflectance spectra. The photocatalytic activity of the as-synthesized Bi2Ti2O7/TiO2 composites was tested in the reduction of aqueous Cr（VI）under visible-light（λ420 nm） irradiation, and compared with that of TiO2 nanoparticles. It was observed that the as-synthesized Bi2Ti2O7/TiO2 composites exhibited much higher photocatalytic activity than TiO2 nanoparticles, and the most efficient composite（300 mg） can achieve the complete reduction of Cr（VI） in 300 mL of 50 mg/L K2Cr2O7 aqueous solution under visible-light（λ420 nm）irradiation in 90 min.展开更多
基金supported by National Water Pollution Control and Treatment Science and Technology Major Project(2018ZX07110003)Key Research and Development Project of Shandong Province(2018CXGC1007)~~
文摘A BiOCl-Bi12O17Cl2 nanocomposite with a high visible-light response and a low photoinduced electron-hole pair recombination rate was successfully synthesized using an ultrasonic-hydrothermal method.The texture,structure,optical,and photocatalytic properties of the composite were characterized.The results showed that the composite had a sheet flower-like structure with a large specific surface area.Ultraviolet-visible diffuse reflection spectra and photoluminescence spectra showed that the composite had an excellent visible-light response and a low recombination rate of photoinduced electron hole pairs.The photocatalytic property of the composite was evaluated by the removal efficiency of rhodamine B and ciprofloxacin under visible-light illumination.The composite’s reaction rate constant of removing rhodamine B(/ciprofloxacin)was approximately 8.14(/4.94),42.63(/11.91)and 64.66(/36.07)times that of Bi12O17Cl2,P25,and BiOCl,respectively.Furthermore,the composite showed a wide applicable pH range and excellent reusability.Mechanism analysis showed that photogenerated holes played a dominant role and·O2–also contributed to photocatalytic degradation.In summary,this study presents a high-efficiency photocatalyst for wastewater treatment.
基金the financial support received from China Postdoctoral Science Foundation Funded Project(No.2018M641387).
文摘This study aimed to explore a new degradation method-photocatalysis technology to polish membrane bioreactor(MBR) effluent, using 2,6-di-tert-butylphenol(2,6-DTBP) as a model soluble microbial product(SMP).2,6-DTBP is one of the predominant SMPs in MBR effluent, which is refractory and difficult to biodegrade.This study developed a novel carboxylated graphene oxide/titanium dioxide/silver(GO-COOH/TiO2/Ag) nanocomposite to photodegrade 2,6-DTBP.GO-COOH/TiO2/Ag was successfully synthesized, using L-cysteine as the linker bonding TiO2/Ag to GO-COOH.The structural, morphological and optical properties of the GO-COOH/TiO2/Ag nanocomposite were characterized using various techniques.Owing to synergistic effects, the GO-COOH/TiO2/Ag nanocomposite exhibited enhanced photocatalytic degradation performance under solar light irradiation when compared to TiO2, Ag and GO-COOH.To remove 25 mg/L 2,6-DTBP, the reaction time for GOCOOH/TiO2/Ag was only 30 min, faster than the 90 min required for pure TiO2 or Ag.In addition, the 200 mg/L GO-COOH/TiO2/Ag nanocomposite aqueous solution showed the best performance under solar light, with 99% removal of 2,6-DTBP.This enhanced capability is likely due to the surface plasmon resonance(SPR) effect contributed by Ag nanoparticles(NPs) doped onto the TiO2.In addition, GO-COOH had a high effective surface area, which assisted in degrading the 2,6-DTBP through improved adsorption.The stability study showed that the photocatalytic activity of the GO-COOH/TiO2/Ag was stable enough for recycling multiple times.The effective degradation performance and excellent stability demonstrates that the GO-COOH/TiO2/Ag nanocomposite can be a promising photocatalyst in the field of effluent SMP photodegradation, which solves the problem of the difficult biodegradation of highly toxic 2,6-DTBP.
基金funded by Natural Science Fund for Colleges and Universities in Jiangsu Province (No. 14KJB430022)the Cultivating project of Xuzhou Institute of Technology (No. XKY2014103)+1 种基金Innovative entrepreneurial training program of college student in Jiangsu province (No. xcx2015043)The Opening Fund of Jiangsu Key Laboratory of Environmental Material and Environmental Engineering
文摘In this work, Bi2Ti2O7/TiO2 composites were synthesized and studied as potential visible-light-activated photocatalysts in the reduction of aqueous Cr（VI）. Bi2Ti2O7/TiO2 composites with tunable compositions were synthesized via a solvothermal-calcination two-step method, simply by changing the molar ratios of Bi（NO3）3·5H2O to tetrabutyl titanate in the reactants. The compositions, structures and optical properties of the as-synthesized Bi2Ti2O7/TiO2 composites were characterized by X-ray diffraction, field emission scanning electron microscopy and UV–vis diffuse reflectance spectra. The photocatalytic activity of the as-synthesized Bi2Ti2O7/TiO2 composites was tested in the reduction of aqueous Cr（VI）under visible-light（λ420 nm） irradiation, and compared with that of TiO2 nanoparticles. It was observed that the as-synthesized Bi2Ti2O7/TiO2 composites exhibited much higher photocatalytic activity than TiO2 nanoparticles, and the most efficient composite（300 mg） can achieve the complete reduction of Cr（VI） in 300 mL of 50 mg/L K2Cr2O7 aqueous solution under visible-light（λ420 nm）irradiation in 90 min.
