Correlation between the acid-base properties of the La2O3 catalyst and its methane reactivity

doi:10.1039/c6cp02459a

	Correlation between the acid-base properties of the La2O3 catalyst and its methane reactivity
	Chu, Changqing 1,2; Zhao, Yonghui 1; Li, Shenggang1,3 ; Sun, Yuhan1,3
	2016-06-28
发表期刊	PHYSICAL CHEMISTRY CHEMICAL PHYSICS (IF:2.9[JCR-2023],3.0[5-Year])
ISSN	1463-9076
卷号	18 期号:24 页码:16509-16517
发表状态	已发表
DOI	10.1039/c6cp02459a
摘要	Density functional theory and coupled cluster theory calculations were carried out to study the effects of the acid-base properties of the La2O3 catalyst on its catalytic activity in the oxidative coupling of methane (OCM) reaction. The La3+-O2- pair site for CH4 activation is considered as a Lewis acid-Bronsted base pair. Using the Lewis acidity and the Bronsted basicity in the fluoride affinity and proton affinity scales as quantitative measures of the acid-base properties, the energy barrier for CH4 activation at the pair site can be linearly correlated with these acid-base properties. The pair site consisting of a strong Lewis acid La3+ site and a strong Bronsted base O2- site is the most reactive for CH4 activation. In addition, the basicity of the La2O3 catalyst was traditionally measured by temperature-programmed desorption of CO2, but the CO2 chemisorption energy is better regarded as a combined measure of the acid-base properties of the pair site. A linear relationship of superior quality was found between the energy barrier for CH4 activation and the CO2 chemisorption energy, and the pair site favorable for CO2 chemisorption is also more reactive for CH4 activation, leading to the conflicting role of the "basicity" of the La2O3 catalyst in the OCM reaction. The necessity for very high reaction temperatures in the OCM reaction is rationalized by the requirement for the recovery of the most reactive acid-base pair site, which unfortunately also reacts most readily with the byproduct CO2 to form the very stable CO32- species.
收录类别	SCI
语种	英语
资助项目	Frontier Science program of Shell Global Solutions International B. V.[PT32281]
WOS研究方向	Chemistry ; Physics
WOS类目	Chemistry, Physical ; Physics, Atomic, Molecular & Chemical
WOS记录号	WOS:000381056500053
出版者	ROYAL SOC CHEMISTRY
WOS关键词	METAL OXIDE CLUSTERS ; RARE-EARTH-OXIDES ; BASIS-SETS ; SURFACE-STATES ; REFLECTANCE SPECTRA ; QUANTUM-CHEMISTRY ; MAGNESIUM-OXIDE ; BASICITY ; ACTIVATION ; PERFORMANCE
原始文献类型	Article
引用统计	正在获取...
文献类型	期刊论文
条目标识符	https://kms.shanghaitech.edu.cn/handle/2MSLDSTB/1796
专题	物质科学与技术学院_特聘教授组_李圣刚组物质科学与技术学院_特聘教授组_孙予罕组
通讯作者	Li, Shenggang
作者单位	1.Chinese Acad Sci, Shanghai Adv Res Inst, CAS Key Lab Low Carbon Convers Sci & Engn, 100 Haike Rd, Shanghai 201210, Peoples R China 2.Univ Chinese Acad Sci, 19 Yuquan Rd, Beijing 100049, Peoples R China 3.ShanghaiTech Univ, Sch Phys Sci & Technol, 100 Haike Rd, Shanghai 201210, Peoples R China
通讯作者单位	物质科学与技术学院
推荐引用方式 GB/T 7714	Chu, Changqing,Zhao, Yonghui,Li, Shenggang,et al. Correlation between the acid-base properties of the La2O3 catalyst and its methane reactivity[J]. PHYSICAL CHEMISTRY CHEMICAL PHYSICS,2016,18(24):16509-16517.
APA	Chu, Changqing,Zhao, Yonghui,Li, Shenggang,&Sun, Yuhan.(2016).Correlation between the acid-base properties of the La2O3 catalyst and its methane reactivity.PHYSICAL CHEMISTRY CHEMICAL PHYSICS,18(24),16509-16517.
MLA	Chu, Changqing,et al."Correlation between the acid-base properties of the La2O3 catalyst and its methane reactivity".PHYSICAL CHEMISTRY CHEMICAL PHYSICS 18.24(2016):16509-16517.