MoS2/Bi2S3复合物的控制合成及其光催化还原水中Cr(Ⅵ)

CONTROLLING PREPARATION AND PROPERTIES OF MoS/BiS COMPOSITE FOR PHOTOCATALYTIC REDUCTION OF Cr(Ⅵ)

采用一步水热法在180℃下制备了花状MoS2/Bi2S3复合异质结。在硫源充足的前提下,通过控制原料中钼源和铋源的比例(Mo∶Bi=0.5,Mo∶Bi=1,Mo∶Bi=1.5),制备了不同负载比的MoS2/Bi2S3复合物。相比于纯Bi2S3,复合物具有更好的光催化还原六价铬活性,并且Mo∶Bi=1的复合物性能最佳,这可能归结于MoS 2优良的吸附性能、MoS2/Bi2S3复合物异质结的构建,极大地提高了光生电子空穴对的分离。本文对复合物的形貌、性能进行了详细的讨论,提出了可能的光催化还原反应的机理。

MoS2/Bi2S3 composite heterojunction was prepared by one-step hydrothermal method at 180℃.Using sufficient sulfur source,MoS2/Bi2S3 composite with different loading ratio was obtained by controlling the proportion of Mo source and Bi source(Mo∶Bi=0.5,Mo∶Bi=1,Mo∶Bi=1.5).Compared with pure Bi2S3,the composites have the better visible light adsorption and higher photocatalytic reduction of hexavalent chromium.Moreover,MoS2/Bi2S3 composite(Mo∶Bi=1)exhibites the best photocatalytic performance,which may be related to the excellent visible light adsorption,the construction of MoS2/Bi2S3 composite heterojunction and high separation rate of electron-hole pairs.Above phenomenea was discussed in detail,and further the possible reaction mechanism of photocatalytic reduction of hexavalent chromium was proposed.