Due to the low concentration of indoor air contaminants, photocatalytic technology shows low efficiency for indoor air purification. The application of TiO2 for photocatalytic removal of formaldehyde is limited, becau...Due to the low concentration of indoor air contaminants, photocatalytic technology shows low efficiency for indoor air purification. The application of TiO2 for photocatalytic removal of formaldehyde is limited, because TiO2 can only absorb ultraviolet （UV） light. Immobilization of TiO2 nanoparticles on the surface of graphene can improve the visible light photocatalytic activity and the adsorption capacity. In this study, rGO （reduced graphene oxide）/TiO2 was synthesized through a hydrotherrnal method using titanium tetrabutoxide and graphene oxide as precursors, and was used for the degradation of low concentration formaldehyde in indoor air under visible light illumination. Characterization of the crystalline structure and morphology of rGO/TiO2 revealed that most GO was reduced to rGO during the hydrothermal treatment, and anatase TiO2 nanoparticles （with particle size of 15-30 nm） were dispersed well on the surface of the rGO sheets, rGO/TiO2 exhibited excellent photocatalyfic activity for degradation of formaldehyde in indoor air and this can be attributed to the role ofrGO, which can act as the electron sink and transporter for separating photo-generated electron-hole pairs through interfacial charge transfer. Furthermore, rGO could adsorb formaldehyde molecules from air to produce a high concentration of formaldehyde on the surface of rGO/ TiO2. Under visible light irradiation for 240 min, the concentration of formaldehyde could be reduced to 58.5 ppbV. rGO/TiO2 showed excellent moisture-resistance behavior, and after five cycles, rGO/TiO2 maintained high photocatalytic activity for the removal of formaldehyde （84.6%）. This work suggests that the synthesized rGO/TiO2 is a promising photocatalyst for indoor formaldehyde removal.展开更多
以硝酸银、磷酸钠为原料,一步沉淀法制备了Ag_3PO_4可见光光催化剂,用硅溶胶将其负载于不锈钢丝网上,经干燥得到光催化电极。以此光催化电极和碳棒分别作为阴极、阳极,在阳极室加入负载生物产电菌的活性炭颗粒,建立光催化耦合微生物燃...以硝酸银、磷酸钠为原料,一步沉淀法制备了Ag_3PO_4可见光光催化剂,用硅溶胶将其负载于不锈钢丝网上,经干燥得到光催化电极。以此光催化电极和碳棒分别作为阴极、阳极,在阳极室加入负载生物产电菌的活性炭颗粒,建立光催化耦合微生物燃料电池反应器。以罗丹明B(RhB)为模型污染物,考察了光照、底物浓度、pH值等对污染物去除效率与电池产电性能的影响。结果显示:在100 W卤素灯光照下、外接500Ω电阻、pH=10、微生物量1.5倍,反应4 h可去除92%的(50 mg·L-1、200 m L)RhB;此时电池输出电压和功率密度分别为124 m V、34.9 mW·m-2。5次重复实验表明该负载型光催化电极具有很好的稳定性。展开更多
报道了可见光促进的邻烯基取代苯甲酰胺的分子内自由基氢胺化反应.在该反应中,通过脱质子光致电子转移策略实现了氮-氢键的直接催化活化来产生氮自由基,随后通过氮自由基与烯烃的加成来实现氢胺化反应.该反应以优异的收率合成了一系列...报道了可见光促进的邻烯基取代苯甲酰胺的分子内自由基氢胺化反应.在该反应中,通过脱质子光致电子转移策略实现了氮-氢键的直接催化活化来产生氮自由基,随后通过氮自由基与烯烃的加成来实现氢胺化反应.该反应以优异的收率合成了一系列具有潜在生理活性的3,4-二氢异喹啉酮衍生物.该反应体系利用有机染料催化剂Eosin Y Na作为光氧化还原催化剂、廉价易得的Na OH作为碱试剂、反应条件温和、操作简单、且官能团兼容性好.另外,该反应在放大量到克级规模、或者利用太阳光作为光源,均能以优异的收率得到相应目标化合物.因此,这类反应为3,4-二氢异喹啉酮的合成提供了一个简便有效的方法.展开更多
基金financially supported by China Postdoctoral Science Foundation(No.2016M592496)Natural Science Foundation of Guangdong Province,China(Nos.2017A030310279,2014A030310431)+1 种基金National Natural Science Foundation of China(Nos.41501319,91645119,21207039,U1201231,51378218,51108187 and 50978103)Guangzhou science and technology plan(No.201607010095)
文摘Due to the low concentration of indoor air contaminants, photocatalytic technology shows low efficiency for indoor air purification. The application of TiO2 for photocatalytic removal of formaldehyde is limited, because TiO2 can only absorb ultraviolet （UV） light. Immobilization of TiO2 nanoparticles on the surface of graphene can improve the visible light photocatalytic activity and the adsorption capacity. In this study, rGO （reduced graphene oxide）/TiO2 was synthesized through a hydrotherrnal method using titanium tetrabutoxide and graphene oxide as precursors, and was used for the degradation of low concentration formaldehyde in indoor air under visible light illumination. Characterization of the crystalline structure and morphology of rGO/TiO2 revealed that most GO was reduced to rGO during the hydrothermal treatment, and anatase TiO2 nanoparticles （with particle size of 15-30 nm） were dispersed well on the surface of the rGO sheets, rGO/TiO2 exhibited excellent photocatalyfic activity for degradation of formaldehyde in indoor air and this can be attributed to the role ofrGO, which can act as the electron sink and transporter for separating photo-generated electron-hole pairs through interfacial charge transfer. Furthermore, rGO could adsorb formaldehyde molecules from air to produce a high concentration of formaldehyde on the surface of rGO/ TiO2. Under visible light irradiation for 240 min, the concentration of formaldehyde could be reduced to 58.5 ppbV. rGO/TiO2 showed excellent moisture-resistance behavior, and after five cycles, rGO/TiO2 maintained high photocatalytic activity for the removal of formaldehyde （84.6%）. This work suggests that the synthesized rGO/TiO2 is a promising photocatalyst for indoor formaldehyde removal.
文摘以硝酸银、磷酸钠为原料,一步沉淀法制备了Ag_3PO_4可见光光催化剂,用硅溶胶将其负载于不锈钢丝网上,经干燥得到光催化电极。以此光催化电极和碳棒分别作为阴极、阳极,在阳极室加入负载生物产电菌的活性炭颗粒,建立光催化耦合微生物燃料电池反应器。以罗丹明B(RhB)为模型污染物,考察了光照、底物浓度、pH值等对污染物去除效率与电池产电性能的影响。结果显示:在100 W卤素灯光照下、外接500Ω电阻、pH=10、微生物量1.5倍,反应4 h可去除92%的(50 mg·L-1、200 m L)RhB;此时电池输出电压和功率密度分别为124 m V、34.9 mW·m-2。5次重复实验表明该负载型光催化电极具有很好的稳定性。
文摘报道了可见光促进的邻烯基取代苯甲酰胺的分子内自由基氢胺化反应.在该反应中,通过脱质子光致电子转移策略实现了氮-氢键的直接催化活化来产生氮自由基,随后通过氮自由基与烯烃的加成来实现氢胺化反应.该反应以优异的收率合成了一系列具有潜在生理活性的3,4-二氢异喹啉酮衍生物.该反应体系利用有机染料催化剂Eosin Y Na作为光氧化还原催化剂、廉价易得的Na OH作为碱试剂、反应条件温和、操作简单、且官能团兼容性好.另外,该反应在放大量到克级规模、或者利用太阳光作为光源,均能以优异的收率得到相应目标化合物.因此,这类反应为3,4-二氢异喹啉酮的合成提供了一个简便有效的方法.
