文献类型：期刊文献

英文题名：Unusual Moisture-Enhanced CO2 Capture within Microporous PCN-250 Frameworks

作者：Chen, Yongwei[1];Qiao, Zhiwei[1,3];Huang, Jiali[2];Wu, Houxiao[1];Xiao, Jing[1];Xia, Qibin[1];Xi, Hongxia[1];Hu, Jun[2];Zhou, Jian[1];Li, Zhong[1]

机构：[1]South China Univ Technol, Sch Chem & Chem Engn, Guangzhou 510640, Guangdong, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[3]Guangzhou Univ, Sch Chem & Chem Engn, Guangzhou 510006, Guangdong, Peoples R China

年份：2018

卷号：10

期号：44

起止页码：38638

外文期刊名：ACS APPLIED MATERIALS & INTERFACES

收录：;EI(收录号：20184406028394);WOS:【SCI-EXPANDED(收录号:WOS:000449887600099)】；

基金：This work was supported by the National Natural Science Foundation of China (nos. 21576092, 21436005, 21676094, and U1662136), the Guangdong Science Foundation (2014A030312007), the Guangdong Province Science and Technology Project (no. 2016A020221006), and Fundamental Research Funds for the Central Universities (2017MS083).

语种：英文

外文关键词：PCN-250; iron-based MOFs; moisture-enhanced CO2 adsorption; gas adsorption; separation

摘要：Developing metal-organic frameworks (MOFs) with moisture-resistant feature or moisture-enhanced adsorption is challenging for the practical CO, capture under humid conditions. In this work, under humid conditions, the CO, adsorption behaviors of two iron-based MOF materials, PCN-250(Fe-3) and PCN-250(Fe2Co), were investigated. An interesting phenomenon is observed that the two materials demonstrate an unusual moisture-enhanced adsorption of CO2. For PCN-250 frameworks, H2O molecule induces a remarkable increase in the CO2 uptake for the dynamic CO2 capture from CO2/N-2 (15:85) mixture. For PCN-250(Fe-3), its CO2 adsorption capacity increases by 54.2% under the 50% RH humid condition, compared with that under dry conditions (from 1.18 to 1.82 mmol/g). Similarly, the CO2 adsorption uptake of PCN-250(Fe2Co) increases from 1.32 to 2.23 mmol/g, exhibiting a 68.9% increase. Even up to 90% RH, for PCN-250(Fe3) and PCN-250(Fe2Co), obvious increases of 43.7 and 70.2% in the CO2 adsorption capacities are observed in comparison with those under dry conditions, respectively. Molecular simulations indicate that the hydroxo functional groups (mu(3)-O) within the framework play a crucial role in improving CO2 uptake in the presence of water vapor. Besides, partial substitution of Fe3+ by Co2+ ions in the PCN-250 framework gives rise to a great improvement in CO2 adsorption capacity and selectivity. The excellent moisture stability (stable even after exposure to 90% RH humid air for 30 days), superior recyclability, as well as moisture-enhanced feature make PCN-250 as an excellent MOF adsorbent for CO2 capture under humid conditions. This study provides a new paradigm that PCN-250 frameworks can not only be moisture resistant but can also subtly convert the common negative effect of moisture to a positive impact on improving CO2 capture performance.