The role of ball milled h-BN in the enhanced photocatalytic activity: A study based on the model of ZnO
The role of ball milled h-BN in the enhanced photocatalytic activity: A study based on the model of ZnO
复制标题
球磨 h-BN 在增强光催化活性中的作用：基于 ZnO 模型的研究
DOI：
10.1016/j.apsusc.2013.05.069
复制
发表时间：
2013-09-01
影响因子：
6.7
通讯作者：
Chen, Shifu
中科院分区：
文献类型：
--
作者：
Fu, Xianliang;Hu, Yingfei;Chen, Shifu
采用球磨法将ZnO与六方氮化硼（h-BN）混合，制备了h-BN/ZnO复合光催化剂。ZnO与球磨h-BN的偶联可以显著提高其光催化降解阳离子染料的活性，同时h-BN的存在也有利于ZnO的稳定性。然而，对于阴离子染料的降解，没有观察到明显的增强作用。结果表明，当h-BN的加入量为1.0wt.%时，球磨时间最佳和20 min。通过XRD、UV-vis DRS、SEM、TEM和对苯二甲酸光致发光探针等表征技术和对比光催化降解实验，发现所观察到的光催化行为可以归因于球磨过程中产生的带负电荷的h-BN。讨论了研磨的h-BN的作用，作为（1）空穴转移促进剂和（2）吸引或排斥位点的带电染料通过静电力的吸附。研究证实，球磨的h-BN可以用作ZnO的空穴转移促进剂。然而，对于特定的降解过程，h-BN/ZnO的最终光催化性能取决于两种效应的叠加。这就是为什么球磨的h-BN的增强仅对阳离子染料有效的原因。(C)2013爱思唯尔有限公司版权所有。
h-BN/ZnO composite photocatalysts were prepared by ball milling of ZnO with hexagonal BN (h-BN). The photocatalytic activity of ZnO for the degradation of cationic dyes could be significantly enhanced by coupling with ball milled h-BN and the stability of ZnO benefited from the presence of h-BN as well. However, for the degradation of anionic dyes, no apparent enhancement was observed. The optimal amount of h-BN and the ball milling time were found to be 1.0 wt.% and 20 min, respectively. Through various characterization techniques (XRD, UV-vis DRS, SEM, TEM, and terephthalic acid photoluminescence probing) and the compared photocatalytic degradation experiments, the observed photocatalytic behaviors could be attributed to the negatively charged h-BN created by the ball milling process. The role of the milled h-BN was discussed to serve as (1) holes-transfer promoter and (2) attractive or repulsive sites for the adsorption of the charged dyes via electrostatic forces. The study confirms that the ball milled h-BN could be used as a holes transfer promoter for ZnO. However, the finial photocatalytic performance of h-BN/ZnO is determined by the superposition of the two effects for a specific degradation process. This is the reason why the enhancement of ball milled h-BN is only effective for cationic dyes. (C) 2013 Elsevier B.V. All rights reserved.