功能模板导向合成介孔三氧化钨及其光电化学性能  

Synthesis by Functional-Template Induced Methodology and Photoelectrochemical Performance of Mesoporous Tungsten Trioxide

作　　者：李东[1] 高彩云[2] LI Dong;GAO Caiyun(School of Material Science and Engineering,North Minzu University,Yinchuan 750021,China;Chemical Science and Engineering College,North Minzu University,Yinchuan 750021,China)

机构地区：[1]北方民族大学材料科学与工程学院,银川750021 [2]北方民族大学化学与化学工程学院,银川750021

出　　处：《人工晶体学报》2020年第12期2350-2357,共8页Journal of Synthetic Crystals

基　　金：北方民族大学2019年重点科研项目(2019KJ02);宁夏自然科学基金(2019AAC03112);北方民族大学中央高校基本科研业务费专项资金(2018XYZCL01)。

摘　　要：以钨酸(H2WO4)为钨前驱体,十二烷胺(DDA)为模板剂,利用模板剂的结构导向功能,合成了比表面积为57.3 m 2·g^-1的介孔三氧化钨(DDA-WO3),是未用DDA制备的非介孔WO3(H2WO4-WO3)的2.35倍。X射线衍射(XRD)结果表明,400℃下煅烧的DDA-WO3是具有单斜晶型结晶孔壁的无序介孔结构。此外,400~550℃下煅烧的DDA-WO3的结晶度均高于同条件的H2WO4-WO3。400℃下的DDA-WO3/FTO(掺氟氧化锡)在1.0 V的Ag/AgCl偏压作用下,可以产生0.18 mA·cm^-2的饱和光电流,是H2WO4-WO3/FTO(0.06 mA·cm^-2)的3倍。增强的光电化学(PEC)活性主要因为DDA-WO3/FTO的大表面积降低了低结晶度对PEC性能的不利影响,成为影响PEC活性的主要因素。500℃煅烧导致了DDA-WO3/FTO介孔结构的坍塌,但高的结晶度仍然保持其优越的PEC催化活性。Mesoporous tungsten trioxide(DDA-WO3)was prepared using tungstic acid(H2WO4)as a tungsten precursor,dodecylamine(DDA)as a surfactant template which has structure guiding function.The specific surface area(57.3 m 2·g^-1)of DDA-WO3 was 2.35 times of 24.5 m 2·g^-1 for WO3(H2WO4-WO3)prepared without DDA.X-ray diffraction(XRD)result of the DDA-WO3 calcined at 400℃indicates that a crystalline framework with disordered arrangement of pores.The crystallinity of DDA-WO3 calcined at 400~550℃is higher than each of H2WO4-WO3.DDA-WO3/FTO(SnO 2∶F)calcined at 400℃generates photoanodic current density of 0.18 mA·cm^-2 at 1.0 V versus Ag/AgCl,which is about 3 times higher than that of the H2WO4-WO3/FTO(0.06 mA·cm^-2).The enhanced photoelectrochemical(PEC)performance of DDA-WO3/FTO suggests that the higher specific surface area of mesoporous structure is a dominant factor for the PEC performance rather than insufficient crystallinity.DDA-WO3/FTO calcined at 500℃still exhibites excellent PEC performance than H2WO4-WO3/FTO due to higher crystallinity,although the degradation of the mesostructure at higher temperature.

关 键 词：介孔结构 模板 三氧化钨 光阳极 光电化学性能 

分 类 号：O614.613[理学—无机化学] TB383[理学—化学]