A simple sol-gel method was employed to prepare gadolinium, nitrogen and sulphur tridoped titania decorated on oxidised multiwalled carbon nanotubes（MWCNT/Gd,N,S-Ti O2）, using titanium（IV） butoxide and thiourea as...A simple sol-gel method was employed to prepare gadolinium, nitrogen and sulphur tridoped titania decorated on oxidised multiwalled carbon nanotubes（MWCNT/Gd,N,S-Ti O2）, using titanium（IV） butoxide and thiourea as titanium and nitrogen and sulphur source, respectively. Samples of varying gadolinium loadings（0.2%, 0.6%, 1.0% and3.0% Gd3＋） relative to titania were prepared to investigate the effect of gadolinium loading and the amounts of carbon nanotubes, nitrogen and sulphur were kept constant for all the samples. Furthermore, the prepared nanocomposites were evaluated for the degradation of naphthol blue black（NBB） in water under simulated solar light irradiation. Higher degradation efficiency（95.7%） was recorded for the MWCNT/Gd,N,S-Ti O2（0.6% Gd）nanocomposites. The higher photocatalytic activity is attributed to the combined effect of improved visible light absorption and charge separation due to the synergistic effect of Gd,MWCNTs, N, S and Ti O2. Total organic carbon（TOC） analysis revealed a higher degree of complete mineralisation of naphthol blue black（78.0% TOC removal） which minimises the possible formation of toxic degradation by-products such as the aromatic amines. The MWCNT/Gd,N,S-Ti O2（0.6% Gd） was fairly stable and could be re-used for five times,reaching a maximum degradation efficiency of 91.8% after the five cycles.展开更多
A series of TiO2 with different crystal phases and morphologies was synthesized via a facile hydrothermal process using titanium nbutoxide and concentrated hydrochloric acid as raw materials. The photocatalytic activi...A series of TiO2 with different crystal phases and morphologies was synthesized via a facile hydrothermal process using titanium nbutoxide and concentrated hydrochloric acid as raw materials. The photocatalytic activity of the samples was evaluated by degradation of Methyl Orange in aqueous solution under UV-Visible light irradiation. On the basis of detailed analysis of the characterizing results of high-resolution transmission electron microscopy, X-ray powder diffraction measurements, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller measurement, it was concluded that the photo-activity of the catalyst is related directly to the 3D morphology and the crystal phase composition. An excellent catalyst should have both a futile 3D flower-like structure and anatase granulous particles. The 3D flower-like structure could enhance light harvesting, as well as the transfer of reactant molecules from bulk solution to the reactive sites on TiO2. In addition, the optimum anatase/rutile phase ratio was found to be 80：20, which is beneficial to the effective separation of the photogenerated electron-hole pairs.展开更多
通过原位沉积法将BiOCl负载到膨胀珍珠岩(EP)孔隙表面,制备出新型漂浮型BiOCl/EP光催化剂,并通过一系列手段对样品进行表征。结果表明,在模拟太阳光照射下,BiOCl/EP复合材料在125 min内对100 mL 15 mg/L罗丹明B溶液的降解率可达95.8%,...通过原位沉积法将BiOCl负载到膨胀珍珠岩(EP)孔隙表面,制备出新型漂浮型BiOCl/EP光催化剂,并通过一系列手段对样品进行表征。结果表明,在模拟太阳光照射下,BiOCl/EP复合材料在125 min内对100 mL 15 mg/L罗丹明B溶液的降解率可达95.8%,远高于纯BiOCl。光催化活性的提高主要归因于BiOCl/EP复合材料中的Bi—O—Si键可作为电子传输通道促进光生电子-空穴对的分离和迁移、更高效的太阳光能利用率以及活性氧物种产生的效率。经过5次连续循环使用后,该复合物的光催化降解效率仍可达到91.0%。展开更多
基金Funding from the University of Johannesburg and DST-NRF Centre of Excellence in Strong Materials is highly appreciated
文摘A simple sol-gel method was employed to prepare gadolinium, nitrogen and sulphur tridoped titania decorated on oxidised multiwalled carbon nanotubes（MWCNT/Gd,N,S-Ti O2）, using titanium（IV） butoxide and thiourea as titanium and nitrogen and sulphur source, respectively. Samples of varying gadolinium loadings（0.2%, 0.6%, 1.0% and3.0% Gd3＋） relative to titania were prepared to investigate the effect of gadolinium loading and the amounts of carbon nanotubes, nitrogen and sulphur were kept constant for all the samples. Furthermore, the prepared nanocomposites were evaluated for the degradation of naphthol blue black（NBB） in water under simulated solar light irradiation. Higher degradation efficiency（95.7%） was recorded for the MWCNT/Gd,N,S-Ti O2（0.6% Gd）nanocomposites. The higher photocatalytic activity is attributed to the combined effect of improved visible light absorption and charge separation due to the synergistic effect of Gd,MWCNTs, N, S and Ti O2. Total organic carbon（TOC） analysis revealed a higher degree of complete mineralisation of naphthol blue black（78.0% TOC removal） which minimises the possible formation of toxic degradation by-products such as the aromatic amines. The MWCNT/Gd,N,S-Ti O2（0.6% Gd） was fairly stable and could be re-used for five times,reaching a maximum degradation efficiency of 91.8% after the five cycles.
基金supported by the National Natural Science Foundation of China(No.20977086,21076196,21177115)the Science and Technology Project of Zhejiang Province,China(No.2012C23026,2011C31041)
文摘A series of TiO2 with different crystal phases and morphologies was synthesized via a facile hydrothermal process using titanium nbutoxide and concentrated hydrochloric acid as raw materials. The photocatalytic activity of the samples was evaluated by degradation of Methyl Orange in aqueous solution under UV-Visible light irradiation. On the basis of detailed analysis of the characterizing results of high-resolution transmission electron microscopy, X-ray powder diffraction measurements, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller measurement, it was concluded that the photo-activity of the catalyst is related directly to the 3D morphology and the crystal phase composition. An excellent catalyst should have both a futile 3D flower-like structure and anatase granulous particles. The 3D flower-like structure could enhance light harvesting, as well as the transfer of reactant molecules from bulk solution to the reactive sites on TiO2. In addition, the optimum anatase/rutile phase ratio was found to be 80：20, which is beneficial to the effective separation of the photogenerated electron-hole pairs.
文摘通过原位沉积法将BiOCl负载到膨胀珍珠岩(EP)孔隙表面,制备出新型漂浮型BiOCl/EP光催化剂,并通过一系列手段对样品进行表征。结果表明,在模拟太阳光照射下,BiOCl/EP复合材料在125 min内对100 mL 15 mg/L罗丹明B溶液的降解率可达95.8%,远高于纯BiOCl。光催化活性的提高主要归因于BiOCl/EP复合材料中的Bi—O—Si键可作为电子传输通道促进光生电子-空穴对的分离和迁移、更高效的太阳光能利用率以及活性氧物种产生的效率。经过5次连续循环使用后,该复合物的光催化降解效率仍可达到91.0%。
