层状钨基氧化物复合材料的合成与电子特性

Synthesis and Electronic Characterization of Organic-tungsten Oxide Hybrid Systems

W_2O_6·H_2O/一元烷基胺复合物[(C_nH_(2n+1)NH_2,n=4、8、12、16)嵌入层状氧化钨W_2O_6·H_2O]的XRD、IR、TG-DSC分析表明:烷基胺C_nH_(2n+1)NH_2能基于质子加合的机制嵌入W_2O_6·H_2O层间,且插层复合物之间烷基胺的插入与抽出是个可逆过程;烷基胺嵌入层间后以全反式构象双层排布,层间距d随烷基胺碳原子数的增加而线性增长,烷基链与层板的夹角为71.6°。插层复合物UV-Vis分析发现,各种复合物的禁带宽度相对半导体氧化钨的禁带宽度变宽了很多,这表明可以通过嵌入不同的物质来调节氧化钨层与层之间的电子传递能力。

Intercalation behavior of n-alkylamines into layered W2O6·H2O has been investigated. W2O6·H2O can accommodate n-alkylamines（CnH2n＋1NH2,n=4,8,12,16）to form intercalation compounds via an acid-base mechanism, and reversible intercalation and deintercalation behavior was observed among DA, （where DA, represents intercalation compounds of W2O6·H2O/CnH2n＋1NH2, and DA4, DA8, DA12, DA16 denote W2O6·H2O/C4H9NH2, W2O6·H2O/C8H17NH2, W2O6·H2O/C12H25NH2, and W2O6·H2O/C16H33NH2, respectively）. The intercalation compounds were characterized by XRD, IR, SEM as well as TG-DSC. The results show that the interlayer distance of intercalation compounds increases with the increase in the number of carbon atoms in the n-alkyl chain, and n-alkylamines exhibit a bilayer arrangement in the interlayer space with a tilt angle of 71.6°. The intercalation of n-alkylamines （CnH2n＋1NH2, n=4, 8, 12, 16） into W2O6·H2O also appears to increase the band-gap energy （Eg） as compared with W2O6·H2O or WO3, but no difference in Eg was observed among DAn, indicating that the oxide layers are electronically decoupled.