Structure-activity relationships in metal organic framework derived mesoporous nitrogen-doped carbon containing atomically dispersed iron sites for CO2 electrochemical reduction
Type
ArticleAuthors
Sun, XiaohuiWang, Riming

Ould-Chikh, Samy

Osadchii, Dmitrii
Li, Guanna
Aguilar, Antonio
Hazemann, Jean-louis
Kapteijn, Freek

Gascon, Jorge

KAUST Department
Chemical Engineering ProgramKAUST Catalysis Center (KCC)
Physical Science and Engineering (PSE) Division
Date
2019-09-25Online Publication Date
2019-09-25Print Publication Date
2019-10Permanent link to this record
http://hdl.handle.net/10754/656926
Metadata
Show full item recordAbstract
Mesoporous nitrogen-doped carbon nanoparticles with atomically dispersed iron sites (named mesoNC-Fe) are synthesized via high-temperature pyrolysis of an Fe containing ZIF-8 MOF. Hydrolysis of tetramethyl orthosilicate (TMOS) in the MOF framework prior to pyrolysis plays an essential role in maintaining a high surface area during the formation of the carbon structure, impeding the formation of iron (oxide) nanoparticles. To gain inside on the nature of the resulting atomically dispersed Fe moieties, HERFD-XANES, EXAFS and valence-to-core X-ray emission spectroscopies have been used. The experimental spectra (both XAS and XES) combined with theoretical calculations suggest that iron has a coordination sphere including a porphyrinic environment and OH/H2O moieties responsible for the high activity in CO2 electroreduction. DFT calculations demonstrate that CO formation is favored in these structures because the free energy barriers of *COOH formation are decreased and the adsorption of *H is impeded. The combination of such a unique coordination environment with a high surface area in the carbon structure of mesoNC-Fe makes more active sites accessible during catalysis and promotes CO2 electroreduction.Citation
Sun, X., Wang, R., Ould-Chikh, S., Osadchii, D., Li, G., Aguilar, A., … Gascon, J. (2019). Structure-activity relationships in metal organic framework derived mesoporous nitrogen-doped carbon containing atomically dispersed iron sites for CO2 electrochemical reduction. Journal of Catalysis, 378, 320–330. doi:10.1016/j.jcat.2019.09.013Sponsors
We thank Alma I. Olivos Suarez for help in the design of the graphical abstract. Mauro Rovezzi is kindly thanked for the extraction of the X-ray emission spectra. Guanna Li thanks the NWO veni grant (no. 016.Veni.172.034). NWO surfsara is acknowledged for providing access to the supercomputer facilities.Publisher
Elsevier BVJournal
Journal of CatalysisAdditional Links
https://linkinghub.elsevier.com/retrieve/pii/S0021951719304439ae974a485f413a2113503eed53cd6c53
10.1016/j.jcat.2019.09.013