交错能带结构钕掺杂钒酸铋形貌与光催化性能调控  

Morphology and Photocatalytic Performance Regulation of Nd^3+-doped BiVO4 with Staggered Band Structure

作　　者：徐晶威 李政 王泽普 于涵 何祺 付念[3] 丁帮福 郑树凯[1] 闫小兵[1] XU Jingwei;LI Zheng;WANG Zepu;YU Han;HE Qi;FU Nian;DING Bangfu;ZHENG Shukai;YAN Xiaobing(College of Electronic Information Engineering,Hebei University,Baoding 071002,China;College of Civil Engineering and Architecture,Hebei University,Baoding 071002,China;College of Physics Science and Technology,Hebei University,Baoding 071002,China)

机构地区：[1]河北大学电子信息工程学院,保定071002 [2]河北大学建筑工程学院,保定071002 [3]河北大学物理科学与技术学院,保定071002

出　　处：《无机材料学报》2020年第7期789-795,共7页Journal of Inorganic Materials

基　　金：河北大学高层次人才基金(521000981118);河北省高等学校科学技术研究项目(ZD2017008);国家自然科学基金(61674050)。

摘　　要：为了研究混合相异质结对光催化的改性机理,以五水硝酸铋、六水硝酸钕、偏钒酸钠为原料,浓硝酸、氢氧化钠为调和剂,水热合成不同浓度钕掺杂钒酸铋样品。X射线衍射和拉曼峰位分析发现,钒酸铋呈现钕浓度依赖的单斜到四方相转变。采用扫描电子显微镜表征发现,这种相变给样品形貌带来巨大变化。小于1at%钕掺杂单斜钒酸铋由不规则颗粒堆积而成,大于7at%钕掺杂四方相由类似球状或凹槽表面果仁状构成,而中间混合相由微米长方体棒状组成。规则形貌导致所有掺杂样品光催化降解罗丹明B效率高于无掺杂样品。高分辨透射电子显微镜和莫特–肖特基测试发现,混合相中形成交错能带异质结,进一步促进光生电-子空穴对分离并抑制其复合,使得4at%钕掺杂样品具有99.4%降解效率。To investigate the modification mechanism of mixed heterogeneous on photocatalysis,a series of Nd^3+-doped BiVO4 photo-catalysts with different Nd3+contents were synthesized through a facile hydrothermal reaction.The samples exhibit Nd3+content-dependent phase transition from monoclinic to tetragonal phase,as demonstrated by XRD and Raman analyses.SEM images show that the phase transition is accompanied by obvious morphology variation.Less than 1at%Nd^3+-doped monocline BiVO4 is composed of irregular particles,while more than 7at%Nd3+doping results in tetragonal phase BiVO4 of sphere-like or kernel with groove surface.When Nd3+content is in the range of 1at%–7at%,the micron cuboid bars appear in the samples.More importantly,monoclinic and tetragonal phase is concomitant in the product and a heterogeneous junction with staggered band structure isformed.The Rhodamine B degradation efficiencies of all Nd^3+-doped samples are higher than those of undoped samples due to the regular morphology after doping.The formed heterogeneous junction inhibits photo-generated electrons and holes recombination of Nd^3+-doped BiVO4,inducing 99.4% catalytic efficiency in 4at%Nd^3+-doped sample.The novel morphology and the intrinsic mechanism of photocatalysis enhancement upon Nd^3+-doped BiVO4 are obtained from the synthesis strategy and the energy band structure.

关 键 词：钒酸铋 交错能带 形貌 光催化降解 

分 类 号：O643[理学—物理化学]