Hierarchical microspheres of a graphene oxide（GO） coupled to N‐doped（BiO）2CO3 composite（N‐BOC‐GO） was synthesized by a simple hydrothermal approach. The N‐BOC‐GO composite gave enhancement in photocatalytic...Hierarchical microspheres of a graphene oxide（GO） coupled to N‐doped（BiO）2CO3 composite（N‐BOC‐GO） was synthesized by a simple hydrothermal approach. The N‐BOC‐GO composite gave enhancement in photocatalytic activity compared to the pure BOC and N‐BOC samples. With 1.0wt% GO, 62% NO removal was obtained with N‐BOC‐GO. The factors enhancing the photocatalytic performance were the high electron‐withdrawing ability and high conductivity of GO and improved visible light‐harvesting ability of N‐BOC‐GO with a 3D hierarchical architecture due to the surface scattering and reflecting（SSR） effect. An effective charge transfer from N‐BOC to GO was demonstrated by the much weakened photoluminescene intensity of the N‐BOC‐GO composite. This work highlights the potential application of GO‐based photocatalysts in air purification.展开更多
Boron-doped diamond （BDD） film electrodes using Ta as substrates were employed for anodic oxidation of salicylic acid （SA）. The effects of operational variables including initial concentration, current density, te...Boron-doped diamond （BDD） film electrodes using Ta as substrates were employed for anodic oxidation of salicylic acid （SA）. The effects of operational variables including initial concentration, current density, temperature and pH were examined. The results showed that BDD films deposited on the Ta substrates had high electrocatalytic activity for SA degradation. There was little effect ofpH on SA degradation. The current efficiency （CE） ,aas fbund to be dependent mainly on the initial SA concentration, current density and temperature. Chemical oxygen demand （COD） was reduced from 830 mg/L to 42 mg/L under a current density of200A/m^2 at 30℃.展开更多
Constructing Z-scheme type photocatalyst is an efficient way to improve the charge separation efficiency and enhance the photocatalytic activity. In this report, the Cd：TiO2 nanoparticles are prepared via the sol-gel...Constructing Z-scheme type photocatalyst is an efficient way to improve the charge separation efficiency and enhance the photocatalytic activity. In this report, the Cd：TiO2 nanoparticles are prepared via the sol-gel route and employed as a starting material. When it was reduced by NaBH4 at 300°C,the surface oxygen vacancies were produced and Cd2＋ was reduced into metal Cd0 nanoparticle（denoted as R-Cd：TiO2）.Subsequently, the formed R-Cd：TiO2 was treated with thioureain the hydrothermal reaction. Through the decomposition of thiourea, the oxygen vacancies were refilled by S2- from thiourea to form S：TiO2/TiO2（d-TiO2） and Cd was partially converted into CdS to form CdS/Cd/d-TiO2 composite. The formed CdS/Cd/d-TiO2 composite exhibits improved photocatalytic activity. Under visible light irradiation（λ〉400 nm）,the H2 production rate of CdS/Cd/d-TiO2 reaches 119 μmol h-1 with 50 mg of photocatalyst without any cocatalyst, which is about 200 and 60 times higher than that of S：TiO2/TiO2（0.57 μmol h-1）, CdS（2.03 μmol h-1） and heterojunction CdS/d-TiO2（2.17 μmol h-1） materials, respectively. The results illustrate that metal Cd greatly promotes the charge separation efficiency due to the formation of Z-scheme type composite. In addition, the photocatalytic activity in the visible light region was dramatically enhanced due to the contribution of both CdS and d-TiO2. The method could be easily extended to other wide bandgap semiconductors for constructing visible light responsive Z-scheme type photocatalysts.展开更多
基金supported by the National Natural Science Foundation of China(21277097)the Key Projects in the National Science&Technology Pillar Program during the 12th Five-Year Plan Period(2012BAJ21B01)~~
文摘Hierarchical microspheres of a graphene oxide（GO） coupled to N‐doped（BiO）2CO3 composite（N‐BOC‐GO） was synthesized by a simple hydrothermal approach. The N‐BOC‐GO composite gave enhancement in photocatalytic activity compared to the pure BOC and N‐BOC samples. With 1.0wt% GO, 62% NO removal was obtained with N‐BOC‐GO. The factors enhancing the photocatalytic performance were the high electron‐withdrawing ability and high conductivity of GO and improved visible light‐harvesting ability of N‐BOC‐GO with a 3D hierarchical architecture due to the surface scattering and reflecting（SSR） effect. An effective charge transfer from N‐BOC to GO was demonstrated by the much weakened photoluminescene intensity of the N‐BOC‐GO composite. This work highlights the potential application of GO‐based photocatalysts in air purification.
文摘Boron-doped diamond （BDD） film electrodes using Ta as substrates were employed for anodic oxidation of salicylic acid （SA）. The effects of operational variables including initial concentration, current density, temperature and pH were examined. The results showed that BDD films deposited on the Ta substrates had high electrocatalytic activity for SA degradation. There was little effect ofpH on SA degradation. The current efficiency （CE） ,aas fbund to be dependent mainly on the initial SA concentration, current density and temperature. Chemical oxygen demand （COD） was reduced from 830 mg/L to 42 mg/L under a current density of200A/m^2 at 30℃.
基金financial support from the National Natural Science Foundation of China (21671011)Beijing High Talent Program+5 种基金Beijing Natural Science Foundation (KZ201710005002)China Postdoctoral Science FoundationBeijing Postdoctoral Research FoundationDongguan Program for International S&T Cooperationsupport from China Scholarship Councilsupported by the National Science Foundation (DMR-1506661, Feng P)
文摘Constructing Z-scheme type photocatalyst is an efficient way to improve the charge separation efficiency and enhance the photocatalytic activity. In this report, the Cd：TiO2 nanoparticles are prepared via the sol-gel route and employed as a starting material. When it was reduced by NaBH4 at 300°C,the surface oxygen vacancies were produced and Cd2＋ was reduced into metal Cd0 nanoparticle（denoted as R-Cd：TiO2）.Subsequently, the formed R-Cd：TiO2 was treated with thioureain the hydrothermal reaction. Through the decomposition of thiourea, the oxygen vacancies were refilled by S2- from thiourea to form S：TiO2/TiO2（d-TiO2） and Cd was partially converted into CdS to form CdS/Cd/d-TiO2 composite. The formed CdS/Cd/d-TiO2 composite exhibits improved photocatalytic activity. Under visible light irradiation（λ〉400 nm）,the H2 production rate of CdS/Cd/d-TiO2 reaches 119 μmol h-1 with 50 mg of photocatalyst without any cocatalyst, which is about 200 and 60 times higher than that of S：TiO2/TiO2（0.57 μmol h-1）, CdS（2.03 μmol h-1） and heterojunction CdS/d-TiO2（2.17 μmol h-1） materials, respectively. The results illustrate that metal Cd greatly promotes the charge separation efficiency due to the formation of Z-scheme type composite. In addition, the photocatalytic activity in the visible light region was dramatically enhanced due to the contribution of both CdS and d-TiO2. The method could be easily extended to other wide bandgap semiconductors for constructing visible light responsive Z-scheme type photocatalysts.
