Effective encapsulation of Ni nanoparticles in metal-organic frameworks and their application for CO2 methanation. (21st May 2019)

• Record Type: Journal Article
• Authors: Mihet, Maria; Grad, Oana; Blanita, Gabriela; Radu, Teodora; Lazar, Mihaela D.
• Is Part Of: International journal of hydrogen energy. Volume 44:Number 26(2019)
• Page Start: 13383
• Page End: 13396
• Publication Date: 2019-05-21
• Subjects: CO2 methanation -- Ni@UiO-66 composite -- Ni@MIL-101 composite -- CO2-TPD -- H2-TPD; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2019.03.259
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Ni(10 wt%)@UiO-66 and Ni(10 wt%)@MIL-101 composites were prepared by the classical impregnation method (IMP) and the "double solvent method" (DS), followed by the rapid and simple reduction of Ni 2+ to Ni 0 by aqueous solution of NaBH4 . Structural characterization by BET, XRD, TGA, SEM/EDX, EELS, XPS showed that Ni nanoparticles of maximum 4 nm are uniformly dispersed on the microporous UiO-66 or the mesoporous MIL-101 support, regardless of the deposition method, without any significant difference in crystallinity and morphology of the MOF support. Functional characterization through temperature programmed desorption of CO2 (CO2 -TPD) reveals an important contribution of the Ni-MOF interaction in the CO2 adsorption capacity. The best catalytic performance in CO2 hydrogenation reaction was obtained in case of the Ni@MIL-101 (IMP) sample: X CO2 of 56.4%, and S CH4 of 91.6% at 320 °C, 4650 h −1 and CO2 :H2 = 1:8. All catalyst samples show stable catalytic performance parameters over a 10 h time on stream. Graphical abstract: Image 1 Highlights: Ni@UiO-66 and Ni@MIL-101 were prepared by impregnation and "double solvent" method. High quality Ni@UiO-66 and Ni@MIL-101 composites were obtained by NaBH4 reduction. NiNPs of maximum 4 nm are well dispersed and stabilized on UiO-66 and MIL-101. Ni-MOF interaction is important in the CO2 adsorption capacity. Ni@MIL-101 (impregnated) presents the best catalytic performance in CO2 methanation.