Mesoporous graphitic carbon nitride materials: synthesis and modifications

Graphitic carbon nitride (g-C₃N₄), as a kind of polymeric semiconductor that has unique electronic structure and excellent chemical stability, has attracted increasing attention of researchers. Moreover, the raw materials for the preparation of g-C₃N₄ are various and easily accessible. All of these have provided favorable advantages for the fast development of g-C₃N₄. Compared to bulk g-C₃N₄, mesoporous g-C₃N₄ has more prominent natures, such as high specific surface area, large pore volume, and the increased amount of surface active sites. Therefore, great efforts have been devoted to develop mesoporous g-C₃N₄ (MCN). Up to now, many methods have been explored for the synthesis of MCN, such as hard-template method, soft-template method, template-free method, sol–gel method, and so on. Among these methods, the hard template method is used most widely. In this paper, the recent research on the synthesis of MCN was reviewed. In addition, the modifications to the obtained MCN, which lead to performance enhancement of the MCN for better applications, were also summarized.     

Biosorption and biodegradation of bisphenol A in an activated sludge system

Research on Chemical Intermediates - Research on biosorption and biodegradation of bisphenol A (BPA) in the environment is crucial for pollutant remediation. In this study, the specific biosorption...     

Increased electroactive species concentration in anodic biofilm of <Emphasis Type="Italic">Geobacter</Emphasis>-inoculated microbial fuel cells under static magnetic field

The effects of a static magnetic field (MF) on the electricity production and anodic bioelectrochemical activity in Geobacter sulfurreducens-inoculated microbial fuel cells (MFCs) were investigated. The results showed that application of a MF of 100, 200, and 400 mT improved the electricity generation considerably, with an increase in the maximum power density by 27–100 %. The maximum power density of 0.030 mW cm^?2 was obtained at field strength of 100 mT, representing the best MFC performance with the lowest internal resistance of 453.6 Ω. Electrochemical impedance spectroscopy results showed that the MFC activation resistance was decreased under a MF. The impact of a MF on the bioelectrochemical activity of Geobacter-based biofilm was analyzed by cyclic voltammetry (CV). The redox peak currents of the voltammetric behavior increased in the presence of a MF, indicating enhanced bioelectrochemical catalyzed activity. In addition, evidence from CV revealed higher density of electroactive species in the anodic biofilm with MF than without, leading to a more efficient direct electron transfer process by G. sulfurreducens.     

薹草属少花薹草组（莎草科）的果囊形态及其系统学意义

用扫描电镜观察了少花薹草组Carex sect. Paniceae （莎草科） 26种3变种的果囊形态和微形态特征。结果表明：（1）果囊形状（喙除外）为倒卵球形、椭球形或卵球形,均为钝三棱状,果囊长度为1.99～7.27 mm,喙多弯曲（仅1种C. striatula果囊的喙直立）,喙急缩或渐缩,喙长与果囊长度的比值为1/8～1/2,表皮细胞多明显隆起,极少数隆起不明显,且多数性状种内保持稳定;（2）喙口形态分斜截、平截、微二齿和二齿4类,且在种内有变异,如C. arakiana、线柄薹草C. filipes、丝柄薹草C. rouyana、C. purpurifera;(3)可根据果囊长度和喙的收缩情况区分部分近缘种,如线柄薹草与少囊薹草C. egena、浙江薹草C. zhejiangensis与显舌薹草C. macroglossa;(4)果囊长度、喙长与果囊长度的比值在sect. Paniceae s.s.与sect. Laxiflorae 2组间有显著差异,对两组的界定有一定价值;（5）被视为组或亚属重要分类性状的果囊横切形状（三棱状或双凸状）在界定少囊薹草组与相关组时无意义,果囊...     

Zirconyl schiff base complex-functionalized MCM-41 catalyzes dehydration of fructose into 5-hydroxymethylfurfural in organic solvents

A heterogeneous catalyst was prepared by immobilizing Zirconyl Schiff base complex on the modified MCM-41 and used in the conversion of fructose to HMF. A higher HMF yield was obtained when fructose as raw material under optimal reaction conditions.     

The preparation,and applications of g-C<Subscript>3</Subscript>N<Subscript>4</Subscript>/TiO<Subscript>2</Subscript> heterojunction catalysts—a review

In recent years, more and more attention has been paid in the research of heterojunction catalysts, due to their better catalytic ability than that of single component catalysts. Up to now, many kinds of heterojunction catalysts have been reported, such as Bi₂O₃/Bi₂WO₆, WO₃/BiVO₄, SnO₂/TiO₂, CdS/TiO₂, Ta₃N₅/Pt/IrO₂ and so on, among which the heterojunction catalyst composed of g-C₃N₄ and TiO₂ has been studied tremendously recently, due to the high activity, high thermal and chemical stability, and well matched energy structure of them. Up to now, many methods have been explored for the synthesis of g-C₃N₄/TiO₂ heterojunction catalysts, such as ball milling of g-C₃N₄ and TiO₂, hydrothermal growth of TiO₂ on g-C₃N₄ and so on. In this review, the recent researches on the synthesis of g-C₃N₄/TiO₂ catalysts were summarized. Moreover, the applications of g-C₃N₄/TiO₂ catalysts in the field of photocatalysis were detailedly introduced.     

Preparation of NiCoP-decorated g-C3N4 as an efficient photocatalyst for H2O2 production

Research on Chemical Intermediates - The development of high-efficiency economic photocatalyst for H2O2 production is of great significance for renewable energy technologies. Here, we use a...     

生物阴极微生物燃料电池

传统微生物燃料电池(microbial fuel cells,MFCs)主要由生物阳极与非生物阴极组成,属于半生物燃料电池,存在化学药剂再生困难、需要铂等贵金属催化及成本高等缺陷。生物阴极则利用微生物参与阴极反应克服了这些缺陷。微生物参与MFCs阴极反应,最初在海底沉积物MFCs中被发现。为了提高空气-生物阴极的产电效率,人们进行了以铁、锰等过渡金属氧化物修饰电极材料的研究。在厌/缺氧环境中,生物阴极可将硝酸盐和硫酸盐等作为最终电子受体。对生物阴极研究的深入为MFCs工业化应用开辟了道路,此外,本文在文献综述的基础上提出了铁锰联合修饰生物阴极材料的可能性。     

g-C3N4 quantum dots-modified mesoporous TiO2–SiO2 for enhanced photocatalysis

Research on Chemical Intermediates - The utilization of TiO2-based photocatalysts for an efficient removal of dye pollutants is limited due to their low surface area, high recombination rate of the...     

可交联嘌呤类脱氧核苷类似物的合成

可交联嘌呤类脱氧核苷是天然脱氧核苷类似物,可与互补链中配对碱基上的胺基发生链间交联反应,导致DNA双链发生不可逆转的交联,对开发核苷类药物和控制修饰基因表达等方面有重要应用。本文开发了一条新的合成路径,该方法以商业化的1-氯-2-脱氧-3,5-二-O-对甲苯甲酰基-D-呋喃核糖为起始原料,经由简便的合成路线制备了目标产...