Effect of vanadium precursors on the structure and catalytic activity of V-OMS-2 for CO oxidation
摘要:
采用简单、低成本回流法制备了未掺杂和不同钒前驱体掺杂V的OMS-2催化剂,考察了其对CO低温氧化的催化活性,并借助XRD,FT-IR,BET,TEM,XPS,TGA和H2-TPR表征技术研究了催化剂的结构、形貌、键态、价态及氧化还原性能.V掺杂改变了OMS-2骨架中锰氧八面体配位氧的配位环境,使OMS-2的形貌发生了显著变化,增加了结构缺陷,加强了表面活性氧的机动性和反应性,使其呈现出远高于未掺杂OMS-2的催化活性.与NaVO3前驱体相比,以V2O5为前驱体掺杂V制备的3%V-OMS-2(1)具有更高的催化活性,可将CO完全燃烧温度从未掺杂OMS-2的200℃降至50℃以下.较大比表面积、特有的孔结构、短纳米棒形貌以及更机动、活泼的表面活性氧是3%V-OMS-2(1)呈现出高CO氧化活性的重要原因.
Undoped and V doped OMS-2 with different V precursors were prepared by a simple and low-cost reflux method,and their catalytic activities for CO oxidation at low temperature were studied.XRD,FT-IR,BET,TEM,XPS,TGA and H2-TPR techniques were employed to characterize the structure,morphology,bond state,valence state and redox performance of the synthesized catalysts.V doping changed the coordination environment of octahedral oxygen in the skeleton of OMS-2,leading to a significant change in the morphology of OMS-2,increased structural defects,enhanced the mobility and reactivity of oxygen species on the surface,thus made them show much higher catalytic activity than undoped OMS-2.Compared with NaVO3as the V precursor,3%V-OMS-2(1)synthesized with V2O5as the V precursor exhibited much higher catalytic activity and it could reduce the temperature of the total combustion of CO from 200℃to lower than 50℃.Large specific surface area,unique pore structure,shorter nanorod morphology and more mobile and active surface oxygen species accounted for the high CO oxidation activity of the 3%V-OMS-2(1).
作者:
汤清虎 郭晓慧 谢小培 赵培正
Tang Qinghu;Guo Xiaohui;Xie Xiaopei;Zhao Peizheng(School of Chemistry and Chemical Engineering,Henan Normal University,Xinxiang 453007,China)
机构地区:
betway官方app 化学化工学院
出处:
《betway官方app 学报:自然科学版》 CAS 北大核心 2022年第4期28-35,共8页
Journal of Henan Normal University(Natural Science Edition)
基金:
国家自然科学基金(21503070) 河南省教育厅科学技术研究重点项目(19A150030)。
关键词:
锰氧八面体分子筛 钒前驱体 掺杂 CO氧化
manganese oxide octahedral molecular sieve vanadium precursor doping CO oxidation
分类号:
O643 [理学—物理化学]