摘要
MXene is a variety of new two-dimensional(2D)materials with early transition metal carbides,nitrides,and carbonitrides.Quantum chemical studies have been carried out on the geometries,electronic structures,stability and catalytic properties of a non-noble metal single-atom catalyst(SAC)with single Co atom anchored on MXene materials of Mo_(2)CS_(2).The Co adatom anchored on top of the Mo atom of this MXene is found to be rather stable,and this SAC is appropriate for CO oxidation.The charge transfers from the surface to the adsorbed CO and O2 play a significant role in the activation of these molecules on Co_(1)/Mo_(2)CS_(2).With this catalyst,the Eley-Rideal(ER),Langmuir-Hinshelwood(LH),and Termolecular Eley-Rideal(TER)mechanisms are explored for CO oxidation.We find that,while all the three mechanisms are feasible at low temperature,Co_(1)/Mo_(2)CS_(2) possesses higher catalytic activity for CO oxidation through the TER mechanism that features an intriguing OC(OO)CO intermediate(IM)adsorbed on Co single atom.The calculated activation energy barriers of the rate-limiting step are 0.67 eV(TER),0.78 eV(LH)and 0.88 eV(ER),respectively.The present study illustrates that it is promising to develop and design low-cost,non-noble metal SACs using MXene types of 2D materials.
MXene是一类由前过渡态金属碳化物、氮化物或碳氮化物构成的新型二维材料.我们利用量子化学方法研究了单原子Co在新型二维MXene材料Mo2CS2上的吸附构型、稳定性和催化性质.研究发现Co原子可以稳定锚定在MXene材料的表面,形成的单原子催化剂适合于催化低温CO氧化.计算表明,吸附的CO和O2分子与Co_(1)/Mo_(2)CS_(2)催化剂表面之间的电荷转移在活化这些小分子时起着重要作用.我们研究了Co1/Mo2CS2催化氧化CO的三种机理:Eley-Rideal(ER),Langmuir-Hinshelwood(LH)和Termolecular Eley-Rideal(TER),发现在低温下这三种反应机理都是可行的.其中在Co_(1)/Mo_(2)CS_(2)催化剂上TER机理具有最高的催化活性,计算的决速步能垒分别为0.67(TER),0.78(LH)和0.88 eV(ER).我们的研究结果表明,利用二维材料MXene发展和设计经济的、非贵金属单原子催化剂具有重要应用前景.
作者
Shamraiz Hussain Talib
Sambath Baskaran
Xiaohu Yu
Qi Yu
Beenish Bashir
Shabbir Muhammad
Sajjad Hussain
Xuenian Chen
Jun Li
Shamraiz Hussain Talib;Sambath Baskaran;于小虎;于琦;Beenish Bashir;Shabbir Mahammad;Sajjad Hussain;陈学年;李隽(Department of Chemistry and Key Laboratory of Organic Optoelectronics&Molecular Engineering of Ministry of Education,Tsinghua University,Beijing,100084,China;Department of Chemistry,Southern University of Science and Technology,Shenzhen,518055,China;Shaanxi Key Laboratory of Catalysis,Shaanxi University of Technology,Hanzhong,723000,China;Research Center for Advanced Materials Sciences(RCAMS),King Khalid University,Abha,61413,P.O.Box 9004,Saudi Arabia;School of Chemistry and Chemical Engineering,Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials,Henan Normal University,Xinxiang,453007,China)
基金
the National Natural Science Foundation of China(21590792,91426302,and 21433005)
Guangdong Provincial Key Laboratory of Catalysis(2020B121201002)
the National Science Basic Research Program of Shaanxi Province(2019JM-226)
the financial and technical support from the Research Center for Advanced Materials Science(RCAMS)at King Khalid University through the Grant(RCAMS/KKU/014-20)。
