For TiO2 heterogeneous reaction, the reaction site and the detailed mechanism are interesting and controversy topics. In this paper, effects of surface fluorination of TiO2 on the photocatalytic degradation of an azo ...For TiO2 heterogeneous reaction, the reaction site and the detailed mechanism are interesting and controversy topics. In this paper, effects of surface fluorination of TiO2 on the photocatalytic degradation of an azo dye, Orange G(OG) under UV or visible light irradiation were investigated, and the possible reaction site and mechanism were elucidated. The adsorption of OG on TiO2 was nearly inhibited by fluoride but its UV light induced photodegradation rate was greatly increased by a factor of about 2.7, which was due to the more generated free hydroxyl radicals. It supported the views that fluoride could desorb the oxidant species from surface and that the reaction sites could move to the bulk solution. In TiO2/Vis system, the observed inhibition effects of fluorination could be interpreted by the competitive adsorption, which provided additional evidences that the visible light sensitized photodegradation of dye pollutants on the catalyst surface.展开更多
Light-driven synthetic micro-/nanomotors have attracted considerable attention in recent years due to their unique performances and potential applications. We herein demonstrate the dye-enhanced self-electrophoretic p...Light-driven synthetic micro-/nanomotors have attracted considerable attention in recent years due to their unique performances and potential applications. We herein demonstrate the dye-enhanced self-electrophoretic propulsion of light-driven Ti O_2–Au Janus micromotors in aqueous dye solutions. Compared to the velocities of these micromotors in pure water, 1.7, 1.5, and 1.4 times accelerated motions were observed for them in aqueous solutions of methyl blue(10-5g L^(-1)), cresol red(10^(-4)g L^(-1)),and methyl orange(10^(-4)g L^(-1)), respectively. We determined that the micromotor speed changes depending on thetype of dyes, due to variations in their photodegradation rates. In addition, following the deposition of a paramagnetic Ni layer between the Au and Ti O_2 layers, the micromotor can be precisely navigated under an external magnetic field. Such magnetic micromotors not only facilitate the recycling of micromotors, but also allow reusability in the context of dye detection and degradation.In general, such photocatalytic micro-/nanomotors provide considerable potential for the rapid detection and ‘‘on-thefly'' degradation of dye pollutants in aqueous environments.展开更多
The effect of Cl^- on photocatalytic degradation(PCD) of pollutants is an important factor since it is ubiquitous in nature. In general, Cl^- showed an inhibition on photodegradation due to its scavenging HO- radica...The effect of Cl^- on photocatalytic degradation(PCD) of pollutants is an important factor since it is ubiquitous in nature. In general, Cl^- showed an inhibition on photodegradation due to its scavenging HO- radicals. In this paper, experiments were carried out to examine the effects of CI on the PCD of Methylene Blue (MB) and Orange II (OII) in aqueous TiO2 suspensions under UV light illumination. It was found that low concentration of Cl^- ( 〈 0.01 mol/L) showed little influence on both dyes, however, high concentration of Cl^- ( 〉 0.10 mol/L) had a very different influence on the decolorization of dyes: a significant inhibition for MB but a great promotion for Oll. In the presence of 0.50 mol/L Cl^- , the rate decreased by 70% for MB while increased 7.5-fold for Oll. Furthermore, two bands in the ultraviolet region of Oll were rapidly broken down. The proposed mechanism was discussed in detail.展开更多
A mild chemistry route was developed to prepare carbonaceous nanofibers-titanium dioxide(CNF-TiO_2) nanocomposites for removal of dye pollutants. In the process of the template-directed hydrothermal carbonization(HTC)...A mild chemistry route was developed to prepare carbonaceous nanofibers-titanium dioxide(CNF-TiO_2) nanocomposites for removal of dye pollutants. In the process of the template-directed hydrothermal carbonization(HTC), ultrathin Te nanowires were adopted as templates and glucose as the carbon source, and TiO_2 was decorated on CNF via the hydrolysis of tetrabutyltitanate in the presence of CNF in ethanol. The as-prepared materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy-dispersive X-ray(EDX) and X-ray diffraction(XRD). SEM and TEM observations displayed that TiO_2 nanoparticles were anchored on the CNF. EDX and XRD data confirmed that the assynthesized samples were CNF-TiO_2, and TiO_2 belonged to anatase titania. Taking advantage of combined benefits of carbonaceous nanofibers and titanium dioxide, these CNF-TiO_2 nanocomposites exhibited higher removal efficiency in a short time and showed good reusability. It was showed that over 97% of Rhodamine B could be removed in 15 min without generating the solid and liquid wastes. The removal efficiency of dyes was still over 80% after reuse in five cycles. All the results demonstrate that the as-prepared CNF-TiO_2 composites are effective materials for fast and effective removal of dye pollutants and thus can provide a new platform for dye decontamination.展开更多
提出以聚苯乙烯树脂为载体的四磺酸酞菁钴催化剂固载化方法,通过聚苯乙烯聚合物中的苯环与酞菁分子上的18π电子大环体发生π-π相互作用,改善四磺酸酞菁钴在过氧化氢存在条件下易自氧化降解的弊端.结果表明,由D201大孔强碱性阴离子交...提出以聚苯乙烯树脂为载体的四磺酸酞菁钴催化剂固载化方法,通过聚苯乙烯聚合物中的苯环与酞菁分子上的18π电子大环体发生π-π相互作用,改善四磺酸酞菁钴在过氧化氢存在条件下易自氧化降解的弊端.结果表明,由D201大孔强碱性阴离子交换树脂负载的四磺酸酞菁钴催化剂催化过氧化氢氧化50mg/L的染料C.I.Acid Blue 25的去除效率可达99%以上,并且循环套用后去除效率保持稳定,有效提高了四磺酸酞菁钴的催化活性与催化寿命.展开更多
基金supported by the National Natural Science Foundation of China(20771010,20801052)National Key Basic Research Program of China(973)(2011CB932601)+1 种基金National High Technology Research and Development Program of China(863)(2007AA03Z311)"100 Talents Program of Chinese Academy of Sciences"(A1010)~~
基金Project(51801235) supported by the National Natural Science Foundation of ChinaProjects(2018RS3019, 2019JJ30033) supported by the Natural Science Foundation of Hunan Province, China+1 种基金Project(2018CX004) supported by the Innovation-Driven Project of Central South University, ChinaProject(502045005) supported by the Start-up Funding of Central South University, China。
文摘For TiO2 heterogeneous reaction, the reaction site and the detailed mechanism are interesting and controversy topics. In this paper, effects of surface fluorination of TiO2 on the photocatalytic degradation of an azo dye, Orange G(OG) under UV or visible light irradiation were investigated, and the possible reaction site and mechanism were elucidated. The adsorption of OG on TiO2 was nearly inhibited by fluoride but its UV light induced photodegradation rate was greatly increased by a factor of about 2.7, which was due to the more generated free hydroxyl radicals. It supported the views that fluoride could desorb the oxidant species from surface and that the reaction sites could move to the bulk solution. In TiO2/Vis system, the observed inhibition effects of fluorination could be interpreted by the competitive adsorption, which provided additional evidences that the visible light sensitized photodegradation of dye pollutants on the catalyst surface.
文摘Light-driven synthetic micro-/nanomotors have attracted considerable attention in recent years due to their unique performances and potential applications. We herein demonstrate the dye-enhanced self-electrophoretic propulsion of light-driven Ti O_2–Au Janus micromotors in aqueous dye solutions. Compared to the velocities of these micromotors in pure water, 1.7, 1.5, and 1.4 times accelerated motions were observed for them in aqueous solutions of methyl blue(10-5g L^(-1)), cresol red(10^(-4)g L^(-1)),and methyl orange(10^(-4)g L^(-1)), respectively. We determined that the micromotor speed changes depending on thetype of dyes, due to variations in their photodegradation rates. In addition, following the deposition of a paramagnetic Ni layer between the Au and Ti O_2 layers, the micromotor can be precisely navigated under an external magnetic field. Such magnetic micromotors not only facilitate the recycling of micromotors, but also allow reusability in the context of dye detection and degradation.In general, such photocatalytic micro-/nanomotors provide considerable potential for the rapid detection and ‘‘on-thefly'' degradation of dye pollutants in aqueous environments.
基金Bureau of Science and Technology of Zhejiang Province(No.2003C33040)
文摘The effect of Cl^- on photocatalytic degradation(PCD) of pollutants is an important factor since it is ubiquitous in nature. In general, Cl^- showed an inhibition on photodegradation due to its scavenging HO- radicals. In this paper, experiments were carried out to examine the effects of CI on the PCD of Methylene Blue (MB) and Orange II (OII) in aqueous TiO2 suspensions under UV light illumination. It was found that low concentration of Cl^- ( 〈 0.01 mol/L) showed little influence on both dyes, however, high concentration of Cl^- ( 〉 0.10 mol/L) had a very different influence on the decolorization of dyes: a significant inhibition for MB but a great promotion for Oll. In the presence of 0.50 mol/L Cl^- , the rate decreased by 70% for MB while increased 7.5-fold for Oll. Furthermore, two bands in the ultraviolet region of Oll were rapidly broken down. The proposed mechanism was discussed in detail.
基金Funded by the National Natural Science Foundation of China(No.21501054)the Collaborative Grant-in-Aid of the HBUT National "111" Center for Cellular Regulation and Molecular Pharmaceutics(No.XBTK-2018003)the Talents Program from Hubei University of Technology(No.BSQD14010)
文摘A mild chemistry route was developed to prepare carbonaceous nanofibers-titanium dioxide(CNF-TiO_2) nanocomposites for removal of dye pollutants. In the process of the template-directed hydrothermal carbonization(HTC), ultrathin Te nanowires were adopted as templates and glucose as the carbon source, and TiO_2 was decorated on CNF via the hydrolysis of tetrabutyltitanate in the presence of CNF in ethanol. The as-prepared materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy-dispersive X-ray(EDX) and X-ray diffraction(XRD). SEM and TEM observations displayed that TiO_2 nanoparticles were anchored on the CNF. EDX and XRD data confirmed that the assynthesized samples were CNF-TiO_2, and TiO_2 belonged to anatase titania. Taking advantage of combined benefits of carbonaceous nanofibers and titanium dioxide, these CNF-TiO_2 nanocomposites exhibited higher removal efficiency in a short time and showed good reusability. It was showed that over 97% of Rhodamine B could be removed in 15 min without generating the solid and liquid wastes. The removal efficiency of dyes was still over 80% after reuse in five cycles. All the results demonstrate that the as-prepared CNF-TiO_2 composites are effective materials for fast and effective removal of dye pollutants and thus can provide a new platform for dye decontamination.
文摘提出以聚苯乙烯树脂为载体的四磺酸酞菁钴催化剂固载化方法,通过聚苯乙烯聚合物中的苯环与酞菁分子上的18π电子大环体发生π-π相互作用,改善四磺酸酞菁钴在过氧化氢存在条件下易自氧化降解的弊端.结果表明,由D201大孔强碱性阴离子交换树脂负载的四磺酸酞菁钴催化剂催化过氧化氢氧化50mg/L的染料C.I.Acid Blue 25的去除效率可达99%以上,并且循环套用后去除效率保持稳定,有效提高了四磺酸酞菁钴的催化活性与催化寿命.