Effective Combination of the Metal Centers in MOF-Based Materials toward Sustainable Oxidation Catalysts

Alexandre M Viana; Francisca Leonardes; Marta C Corvo; Salete S Balula; Luís Cunha-Silva

doi:10.3390/ma16083133

Effective Combination of the Metal Centers in MOF-Based Materials toward Sustainable Oxidation Catalysts

Materials (Basel). 2023 Apr 16;16(8):3133. doi: 10.3390/ma16083133.

Authors

Alexandre M Viana¹, Francisca Leonardes¹, Marta C Corvo², Salete S Balula¹, Luís Cunha-Silva¹

Affiliations

¹ LAQV-REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal.
² CENIMAT/I3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.

Abstract

A successful encapsulation of Keggin-type polyoxomolybdate (H₃[PMo₁₂O₄₀], PMo₁₂) into metal-organic framework (MOF) materials with an identical framework but distinct metal centers (ZIF-8 with Zn²⁺ and ZIF-67 with Co²⁺) was accomplished by a straightforward room-temperature procedure. The presence of Zn²⁺ in the composite material PMo₁₂@ZIF-8 instead of Co²⁺ in PMo₁₂@ZIF-67 caused a remarkable increase in the catalytic activity that achieved a total oxidative desulfurization of a multicomponent model diesel under moderate and friendly conditions (oxidant: H₂O₂ and solvent: ionic liquid, IL). Interestingly, the parent ZIF-8-based composite with the Keggin-type polyoxotungstate (H₃[PW₁₂O₄₀], PW₁₂), PW₁₂@ZIF-8, did not show the relevant catalytic activity. The ZIF-type supports present an appropriate framework to accommodate active polyoxometalates (POMs) into their cavities without leaching, but the nature of the metallic center from the POM and the metal present in the ZIF framework were vital for the catalytic performance of the composite materials.

Keywords: heterogeneous catalysis; nanocomposite material; oxidative desulfurization; polyoxometalates; zeolitic imidazolate frameworks.

Grants and funding

This research work received financial support from Portuguese national funds (FCT/MCTES, Fundação para a Ciência e Tecnologia and Ministério da Ciência, Tecnologia e Ensino Superior) through the strategic project UIDB/50006/2020 (for LAQV-REQUIMTE), LA/P/0037/2020, UIDP/50025/2020, UIDB/50025/2020 (for I3N), and ROTEIRO/0031/2013 – PINFRA/22161/2016 (for PTNMR). The work also received funding from the European Union (FEDER funds through COMPETE POCI-01-0145-FEDER- 031983).