为了研究满足压载水排放标准的处理系统,建立了可以实现单独控制的以钛基氧化锡钌(Ti/SnO2-RuO2)为阳极材料的电催化系统和紫外辐射复合压载水处理系统。以杜氏盐藻、青岛大扁藻、锥状克里斯普藻和四爿藻为目标处理微生物,对该系统进行...为了研究满足压载水排放标准的处理系统,建立了可以实现单独控制的以钛基氧化锡钌(Ti/SnO2-RuO2)为阳极材料的电催化系统和紫外辐射复合压载水处理系统。以杜氏盐藻、青岛大扁藻、锥状克里斯普藻和四爿藻为目标处理微生物,对该系统进行微藻灭活实验结果表明,Ti/SnO2-RuO2阳极电催化-UV复合系统克服了单独电催化系统高能耗、单独紫外辐射系统紫外灯衰减迅速的缺点,在紫外辐射出度45μW/cm2、电流密度130 m A/cm2、HRT为1.0 s的条件下,处理出水4 h后活藻数量可以达到国际海事组织(IMO)对压载水中10~50μm微生物的灭活要求。总剩余氧化物(TRO)含量会随时间推移而有衰减,且没有出现细胞光复活和修复现象,说明该复合系统具有理想的持续灭活作用。展开更多
β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic syst...β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst.展开更多
文摘为了研究满足压载水排放标准的处理系统,建立了可以实现单独控制的以钛基氧化锡钌(Ti/SnO2-RuO2)为阳极材料的电催化系统和紫外辐射复合压载水处理系统。以杜氏盐藻、青岛大扁藻、锥状克里斯普藻和四爿藻为目标处理微生物,对该系统进行微藻灭活实验结果表明,Ti/SnO2-RuO2阳极电催化-UV复合系统克服了单独电催化系统高能耗、单独紫外辐射系统紫外灯衰减迅速的缺点,在紫外辐射出度45μW/cm2、电流密度130 m A/cm2、HRT为1.0 s的条件下,处理出水4 h后活藻数量可以达到国际海事组织(IMO)对压载水中10~50μm微生物的灭活要求。总剩余氧化物(TRO)含量会随时间推移而有衰减,且没有出现细胞光复活和修复现象,说明该复合系统具有理想的持续灭活作用。
基金the National Natural Science Foundation of China under Grant 21473183the open fund of Key Laboratory of Computational Physical Sciences(Fudan University),Ministry of Education.
文摘β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst.
