有机胺表面修饰的一维CdSe_(0.8)S_(0.2)-DETA/二维SnNb_(2)O_(6)S型异质结及其可见光光催化CO_(2)还原性能

近年来,随着人口的增加,汽车尾气的排放和化石燃料的燃烧加剧,大气中的二氧化碳含量持续增加.光催化技术是根本上解决上述问题的有效方法之一.但目前光催化技术存在催化效率低、载流子易复合等缺点.二维SnNb_(2)O_(6)纳米片能够有效缩短光生电子从材料内部到材料表面的传输距离,减少电子和空穴在光催化剂中的复合.但SnNb_(2)O_(6)的带隙较宽,导致可见光吸收率较低,而且在单一的半导体材料中,强氧化还原能力和高可见光吸收能力难以共存.CdSe_(x)S_(1-x)-DETA是一种直接带隙半导体,在可见光范围内可调节带隙.为了提高SnNb_(2)O_(6)的光催化活性和光吸收范围,在两种半导体材料之间设计异质结是一种有效的方法.其中,梯型(S型)异质结可以有效促进光生电子-空穴对的分离和转移,并保持强大的氧化和还原能力,在有效降低电子空穴对的复合速率的同时,增强光催化剂的活性和稳定性.本文通过溶剂热法设计制备了S型Cd Se_(0.8)S_(0.2)-DETA/SnNb_(2)O_(6)异质结构材料,利用X射线衍射(XRD)可以观察到除Cd Se_(0.8)S_(0.2)-DETA和SnNb_(2)O_(6)物相外,没有其它组分.采用扫描电子显微镜和透射电子显微镜(TEM)进一步观察了光催化剂的结构和形貌,结果表明,一维的Cd Se_(0.8)S_(0.2)-DETA生长在二维SnNb_(2)O_(6)纳米片上;能谱分析也证实该催化剂仅包含Cd Se_(0.8)S_(0.2)-DETA和SnNb_(2)O_(6)中的元素,无其它杂质;TEM的晶格条纹进一步表明两种物质是复合在一起的,不是机械的混合物.紫外可见光漫反射光谱(UV-Vis)结果表明,Cd Se_(0.8)S_(0.2)-DETA和SnNb_(2)O_(6)的吸收带边分别为1.71和2.52 e V.随着复合样品中Cd Se_(0.8)S_(0.2)-DETA含量的增加,其可见光吸收范围增大.光电流和阻抗响应图谱表明,Cd Se_(0.8)S_(0.2)-DETA/SnNb_(2)O_(6)复合材料具有较高的光响应和较低的阻抗,有利于电子空穴的运输.光催化CO_(2)还原测试结果表明,30%Cd Se_(0.8)S_(0.2)-DETA/SnNb_(2)O_(6)催化CO_(2)还原生成CO的产率(17.31μmol·g^(-1)·h^(-1))最高,分别是SnNb_(2)O_(6)(6.2μmol·g^(-1)·h^(-1))和Cd Se_(0.8)S_(0.2)-DETA(3.6μmol·g^(-1)·h^(-1))的2.8倍和4.8倍.XRD测试结果表明,反应后光催化剂的与新鲜光催化剂的衍射峰基本相符.催化剂经过4次循环测试后催化性能基本稳定,说明光催化剂具有较好的稳定性.XPS表征结果显示,相对于纯的Cd Se_(0.8)S_(0.2)-DETA与SnNb_(2)O_(6),复合材料中Cd,Se与S的结合能降低,周围的电子密度增大,而复合材料中Sn,Nb与O的结合能增加,周围的电子密度降低,这表明电子从SnNb_(2)O_(6)到Cd Se_(0.8)S_(0.2)-DETA的转移路径遵循S型异质结机理.综上,本文提供了一种简单的制备S型光催化方法,可以优化能带结构以促进光生载流子的分离,从而实现高效率的二氧化碳还原.

Fungal diversity notes 253-366:taxonomic and phylogenetic contributions to fungal taxa

Notes on 113 fungal taxa are compiled in this paper,including 11 new genera,89 new species,one new subspecies,three new combinations and seven reference specimens.Awide geographic and taxonomic range of fungal taxa are detailed.In the Ascomycota the new genera Angustospora(Testudinaceae),Camporesia(Xylariaceae),Clematidis,Crassiparies(Pleosporales genera incertae sedis),Farasanispora,Longiostiolum(Pleosporales genera incertae sedis),Multilocularia(Parabambusicolaceae),Neophaeocryptopus(Dothideaceae),Parameliola(Pleosporales genera incertae sedis),and Towyspora(Lentitheciaceae)are introduced.Newly introduced species are Angustospora nilensis,Aniptodera aquibella,Annulohypoxylon albidiscum,Astrocystis thailandica,Camporesia sambuci,Clematidis italica,Colletotrichum menispermi,C.quinquefoliae,Comoclathris pimpinellae,Crassiparies quadrisporus,Cytospora salicicola,Diatrype thailandica,Dothiorella rhamni,Durotheca macrostroma,Farasanispora avicenniae,Halorosellinia rhizophorae,Humicola koreana,Hypoxylon lilloi,Kirschsteiniothelia tectonae,Lindgomyces okinawaensis,Longiostiolum tectonae,Lophiostoma pseudoarmatisporum,Moelleriella phukhiaoensis,M.pongdueatensis,Mucoharknessia anthoxanthi,Multilocularia bambusae,Multiseptospora thysanolaenae,Neophaeocryptopus cytisi,Ocellularia arachchigei,O.ratnapurensis,Ochronectria thailandica,Ophiocordyceps karstii,Parameliola acaciae,P.dimocarpi,Parastagonospora cumpignensis,Pseudodidymosphaeria phlei,Polyplosphaeria thailandica,Pseudolachnella brevifusiformis,Psiloglonium macrosporum,Rhabdodiscus albodenticulatus,Rosellinia chiangmaiensis,Saccothecium rubi,Seimatosporium pseudocornii,S.pseudorosae,Sigarispora ononidis and Towyspora aestuari.New combinations are provided for Eutiarosporella dactylidis(sexual morph described and illus trated)and Pseudocamarosporium pini.Descriptions,illustrations and/or reference specimens are designated for Aposphaeria corallinolutea,Cryptovalsa ampelina,Dothiorella vidmadera,Ophiocordyceps formosana,Petrakia echinata,Phragmoporthe conformis and Pseudocamarosporium pini.The new species of Basidiomycota are Agaricus coccyginus,A.luteofibrillosus,Amanita atrobrunnea,A.digitosa,A.gleocystidiosa,A.pyriformis,A.strobilipes,Bondarzewia tibetica,Cortinarius albosericeus,C.badioflavidus,C.dentigratus,C.duboisensis,C.fragrantissimus,C.roseobasilis,C.vinaceobrunneus,C.vinaceogrisescens,C.wahkiacus,Cyanoboletus hymenoglutinosus,Fomitiporia atlantica,F.subtilissima,Ganoderma wuzhishanensis,Inonotus shoreicola,Lactifluus armeniacus,L.ramipilosus,Leccinum indoaurantiacum,Musumecia alpina,M.sardoa,Russula amethystina subp.tengii and R.wangii are introduced.Descriptions,illustrations,notes and/or reference specimens are designated for Clarkeinda trachodes,Dentocorticium ussuricum,Galzinia longibasidia,Lentinus stuppeus and Leptocorticium tenellum.The other new genera,species new combinations are Anaeromyces robustus,Neocallimastix californiae and Piromyces finnis from Neocallimastigomycota,Phytophthora estuarina,P.rhizophorae,Salispina,S.intermedia,S.lobata and S.spinosa from Oomycota,and Absidia stercoraria,Gongronella orasabula,Mortierella calciphila,Mucor caatinguensis,M.koreanus,M.merdicola and Rhizopus koreanus in Zygomycota.