Bi系光催化材料结构调控方法及其在环境能源领域的应用研究进展

Bi系光催化材料是近年来被广泛研究的一类新型光催化剂,具有独特的层状结构和合适的带隙,价导带位置可调,是一类性能优异、环境友好型、结构可调的光催化剂,在环境与能源领域具有广阔的应用前景。本文介绍了Bi系光催化材料的种类,系统综述了形貌调控、表面缺陷引入、晶面构建、表面等离子体修饰、元素掺杂、构建异质结等结构调控方法,分析了光催化性能增强作用机制,并重点总结了铋系光催化材料在水处理、空气净化、固氮、产氢等环境净化和能源转化领域的应用研究进展,最后讨论了该领域所面临的挑战,并对Bi系光催化材料未来的发展进行了展望。     

光催化活性纳米TiO2的固定与催化降解甲基橙研究

纳米TiO2具有很好的光催化活性,对比研究了玻璃纤维、多孔硅胶、S iO2、分子筛等作为载体材料对纳米TiO2的固定,比较了各种材料对纳米TiO2的负载量及负载条件,相对来说,玻璃纤维的负载量最大。以甲基橙为模拟物,测定了各种固定化纳米TiO2的光催化性能,负载量最大的玻璃纤维表现出最好的催化活性。     

氧化亚铜内嵌碳纳米管复合球的合成及光催化性能研究

采用溶液法原位制备了氧化亚铜内嵌碳纳米管(Cu2O/MWNTs)复合球. 通过扫描电子显微镜（SEM）, 透射电子显微镜(TEM), 紫外光度分析仪对复合球进行了形貌分析和性能检测.结果表明:碳纳米管均匀嵌镶在Cu2O球内部; 比较了Cu2O和氧化亚铜内嵌碳纳米管(Cu2O/MWNTs)复合球对对硝基苯酚的光催化效果, Cu2O复合球对对硝基苯酚溶液的光催化降解率高出氧化亚铜10%左右.     

Study on Active Oxygen Quantum Yield, Insecticidal Activities and Stability of Diphenylthiophene

Active oxygen quantum yield, insecticidal activities and stability of diphenylthiophene were studied for the first time. The results showed that maximum diphenylthiophene absorbency variety was 0.438 after irradiation for 280 min and that of α-terthienyl (α-T) was 0.480 after irradiation for 200 min with UV. LC50 values ofdiphenylthiophene and α-T against 3rd instar larvae of Aedes albopictus were 9.18 × 10-3 and 9.69 × 10-4 μg mL-1 when treated for 24 h, respectively. LC50 values of the two chemicals against the 3rd instar larvae of Plutella xylostella were 267.87 and 222.22 μg mL-1 when treated for 24 h, respectively. The half lives of diphenylthiophene and α-T in methanol were 113.62 and 10.65 h. Difference between quantum yield of diphenylthiophene and α-T was not significant and they all possessed high toxicity to Aedes albopictus and Plutella xylostella, but diphenylthiophene was more stable than α-T. It could be concluded that diphenylthiophene has overcome the deficiency of photoactivated insecticides which degraded quickly in the environment and could not be applied on the field. Diphenylthiophene could kill the insects and accelerate the degradation rate of triazophos. The benefits of diphenylthiophene can be further exploited and applied on the field.     

60Co-g辐照改性银掺杂纳米TiO2及光催化降解乙烯

为了解60Co-射线辐照且以活性炭纤维(ACF)为载体所负载TiO2的半导体材料(TiO2/ACF)对光催化降解冷藏环境中乙烯的影响,该文拟采用60Co-辐照制备纳米Ag沉积的TiO2/ACF(Ag-TiO2/ACF)光催化材料,在模拟园艺产品的冷藏环境中,进行了3种不同膜的光催化降解乙烯效果的研究,并利用场发射扫描电镜(FESEM)、透射电子显微镜(TEM)、X射线衍射仪(XRD)对所制备的光催化材料进行相关的表征分析。结果表明:在加入分散剂聚乙烯吡咯烷酮后,60Co-辐照能使Ag颗粒较好地负载在TiO2上,TiO2均匀分散在ACF膜上而不发生团聚,且TiO2颗粒晶相改变、尺寸变小,有助于提高Ag-TiO2/ACF的催化效率。Ag-TiO2/ACF光催化降解乙烯的效果用一级动力学速率方程描述;经辐照制备的Ag-TiO2/ACF薄膜比未辐照的TiO2/ACF和辐照的TiO2/ACF薄膜光催化降解乙烯的反应速率常数分别提高了44%和37%。研究结果为TiO2光催化技术的进一步的应用提供了参考。     

己唑醇的光化学降解

以低压汞灯为光源研究了己唑醇在溶液中的光化学降解。结果表明,在365 nm紫外光照射下,己唑醇在正己烷中很稳定,说明己唑醇在自然光下难以降解;在254 nm光照下己唑醇在丙酮、水、甲醇、乙酸乙酯、正己烷中发生光解,不同溶剂中的光解速率为:甲醇>正己烷>乙酸乙酯>水>丙酮。FeCl3、H2O2、FeCl3-H2O2、β-环糊精等光催化剂能加快己唑醇在紫外光下的降解,在本研究条件下,其催化能力为FeCl3-H2O2>β-环糊精>H2O2>FeCl3。对降解机理进行分析,认为己唑醇在溶液中是通过产生羟基自由基(HO·)而发生光解的。     

纳米TiO2光催化降解苹果和洋李中毒死蜱残留的效果研究

为了利用光催化降解剂降低甚至消除农产品的农药残留,解决食品安全问题。本研究以水果中的有机磷农药残留为研究对象,探索了纳米TiO2粉体和水凝胶对苹果和洋李中毒死蜱残留的光催化降解效果。结果表明：二者均能很好的降解苹果和洋李中的毒死蜱残留,TiO2水凝胶的光催化效果稍优于纳米TiO2粉体。纳米TiO2本身无毒,光催化活性高,作为光催化降解剂在降低或消除农产品中的有机磷农药残留这一领域具有广阔的发展前景。     

TiO2 Photocatalysis and its Effect of Sterilizing and Killing Bacterium in Low Temperature Equipment

Some small particles can be produced from TiO 2 by using photocatalytic reaction. These small particles have high oxidation ability and can be usedi n refrigeration equipments in order to sterilize and kill bacterium. The principle of TiO 2 photocatalysis and the actions of sterilizing and killing bcterium were introduced. It is explained that different structures of TiO 2 have different photocatalytic performances and clarify the ways of combining large band gap semiconductor with small band gap semiconductor and doping impurity to enhance TiO 2 photocatalytic efficiency. Some problems of TiO 2 photocatalysis and application prospects were put forward.     

纳米TiO2光催化材料及其在净化大气污染中的应用

纳米TiO2光催化技术作为一种新兴的治理污染技术,被誉为21世纪的"光净化革命"。介绍了纳米TiO2光催化材料的特性、光催化反应原理以及在净化大气污染方面的应用进展。     

氢氧化铟/活性炭协同吸附-光催化复合材料的制备及其甲苯降解性能

以In(NO_3)_3·4.5H_2O和六亚甲基四胺(HMT)为起始物,以活性炭(AC)为载体,采用一步水热原位合成法制备In(OH)_3/AC协同吸附-光催化复合材料,采用XRD、FT-IR、DRS、SEM以及TEM等方法对复合材料的晶相结构、表面结构等进行了表征,并测试了复合材料对甲苯的光催化降解性能。结果表明,AC与In(OH)_3是采用化学键结合;AC的加入不仅影响了In(OH)_3的成核与熟化过程,改变了In(OH)_3的晶胞结构,使晶面间距变小、粒径增加,而且降低了其结晶度;但是AC仅影响复合材料对光的吸收强度,对In(OH)_3能阈结构和粒子形貌基本没有影响。复合材料对甲苯的光催化降解测试结果显示,加入适量的AC(3%)所产生的吸附-催化协同效应可以有效地提高材料的光催化性能,光照60 min时,甲苯的降解率可达98.25%。