摘要
采用气相辅助的离子置换法,合成了Cu、Mn双金属有机骨架(MOF)材料,通过控制煅烧条件制备了一系列CuO-Cu_(1.5)Mn_(1.5)O_(4)复合氧化物,研究了不同n(Mn)/n(Cu)对丙烷催化燃烧性能的影响。结果表明:随着n(Mn)/n(Cu)提高,CuO-Cu_(1.5)Mn_(1.5)O_(4)催化丙烷燃烧能力增强,当n(Mn)/n(Cu)为31∶69时,催化剂对丙烷的完全燃烧温度(T_(90))仅为309.8℃,催化活性远高于CuO和Mn_(2)O_(3)。表征和密度泛函理论(DFT)计算结果表明,由于Mn和Cu的相互作用,复合氧化物表面具有更高的n(Mn^(4+))/n(Mn^(3+))和n(Cu^(+))/n(Cu^(2+)),从而增强了催化剂的低温还原性能。并且n(Cu^(+))/n(Cu^(2+))提高导致催化剂中氧空位浓度升高,更容易吸附活化O_(2)、丙烷分子,增强了催化剂的丙烷燃烧性能。
In the paper,Cu and Mn bimetallic organic framework materials were prepared using the gas-assisted ion replacement method.A series of CuO-Cu_(1.5)Mn_(1.5)O_(4) composite oxides were prepared through controlled calcination,and the effect of various n(Mn)/n(Cu)on the catalytic performance of propane total oxidation was studied.The results revealed that with an increase in the n(Mn)/n(Cu),CuO-Cu_(1.5)Mn_(1.5)O_(4) catalysts showed enhanced propane total oxidation catalytic activities.When n(Mn)/n(Cu)was 31∶69,the complete combustion temperature(T_(90))of propane was just 309.8℃,signifying that the activity was much higher than that of CuO and Mn_(2)O_(3).The experimental and density functional theory(DFT)calculation results revealed that the synergetic effect of Mn and Cu increased the n(Mn^(4+))/n(Mn^(3+))and n(Cu^(+))/n(Cu^(2+))on the surface,which enhanced the redox ability at low-temperature.Meanwhile,the increase of n(Cu^(+))/n(Cu^(2+))led to a higher concentration of oxygen vacancies,and made it easier to adsorb and activate oxygen and propane molecules on the surface,thereby boosted the propane catalytic oxidation performance.
作者
冯超
熊高燕
汪云霞
潘原
柳云骐
FENG Chao;XIONG Gaoyan;WANG Yunxia;PAN Yuan;LIU Yunqi(Collge of Chemical Engineering,China University of Petroleum(East China),Qingdae 266580,China)
出处
《环境工程》
CAS
CSCD
北大核心
2022年第8期69-77,共9页
Environmental Engineering
基金
国家自然科学基金(21878334)
山东省泰山学者青年专家人才项目(tsqn201909065)。
