脱硝催化剂中金属Cu的价态变化及其影响因素的XPS研究  

Study on Chemical State of Copper in De-NO_x Catalyst and Its Influencing Factors by X-ray Photoelectron Spectrometry

作　　者：陈静允 王红妍 马琳鸽 王宝冬 CHEN Jing-yun;WANG Hong-yan;MA Lin-ge;WANG Bao-dong(National Institute of Clean-and-Low-Carbon Energy,Beijing 102209,China)

机构地区：[1]北京低碳清洁能源研究所,北京102209

出　　处：《分析测试学报》2018年第3期336-340,共5页Journal of Instrumental Analysis

基　　金：青年千人启动基金项目(GB9300120001)

摘　　要：考察了X射线光电子能谱(XPS)测试过程中金属Cu改性钒基脱硝催化剂在X射线照射下Cu元素的价态变化及影响因素。结果表明,催化剂中Cu元素以Cu O(Cu2+)和Cu2O(Cu+)两种形式存在,X射线照射会引起Cu O的还原;且初始测得的Cu2O主要为样品焙烧后本征存在的物质。样品中Cu元素还原(Cu O转化为Cu2O)受X射线照射时间与功率、Cu负载量以及样品制备方法等因素的影响:随着照射时间的增加或X射线功率的提高,Cu O还原率均逐渐升高;随着Cu负载量的升高,Cu O还原率整体呈下降趋势,但当负载量达3%后,Cu O的绝对变化量与Cu负载量几乎无关(维持在~1.2%);制备方法中活性组分V元素的存在提高了Cu O的还原活性,而草酸的添加降低了其还原活性。该研究为Cu改性钒基脱硝催化剂的表征分析提供了重要参考,也为其它类似敏感样品的XPS分析提出了测试条件及方法上的建议。The chemical state variation of Cu element and its influencing factors on Cu modified vanadium-based de-NO x catalyst were investigated by X-ray photoelectron spectrometry(XPS).The results showed that Cu element in catalyst existed in the forms of CuO and Cu 2O,and CuO could be reduced under X-ray irradiation.However,the initially observed Cu 2O was mainly derived from the prepared samples other than generated by X-ray.The influencing factors for the reduction from CuO to Cu 2O included the irradiation time and power of X-ray,copper load and sample preparation methods,etc.The results indicated that the reduction percentage for CuO increased gradually with the increase of irradiation time or power of X-ray.In general,the reduction percentage for CuO decreased with the increase of Cu load.The reduction percentage for CuO keeped at the level about 1.2%when the Cu load reached to 3%.The existence of the active component vanadium increased the reduction activity of CuO,while the addition of oxalic acid reduced the reduction activity.This study provided an important reference for the characterization and analysis of Cu modified vanadium denitrification catalyst,and also gave some suggestions for parameter settings and analysis method for other similar X-ray sensitive samples.

关 键 词：X射线光电子能谱(XPS) Cu改性钒基脱硝催化剂 CUO CU 2O 还原 

分 类 号：O657.62[理学—分析化学]