MOFs based on ZIF-8 deposited on TiO2 nanotubes increase the surface adsorption of CO2 and its photoelectrocatalytic reduction to alcohols in aqueous media

Author(s)

Cardoso, J. C. ^[1] ; Stulp, S. ^[2] ; de Brito, J. F. ^[1] ; Flor, J. B. S. ^[1] ; Frem, R. C. G. ^[1] ; Zanoni, M. V. B. ^[1]

Affiliation

^[1] Sao Paulo State Univ UNESP, Inst Chem, Araraquara - Brazil

^[2] Univ Vale Taquari UNIVATES, Ctr Sci & Engn Lajeado, Lajeado - Brazil

• Document type: Journal article
• Source: APPLIED CATALYSIS B-ENVIRONMENTAL; v. 225, p. 563-573, JUN 5 2018.
• Web of Science Citations: 25

Abstract

This work describes, the decoration of Ti/TiO2 nanotubes by nanoparticles of ZIF-8 (zeolite imidazole framework-8) grown using a layer-by-layer process. Morphological and crystallographic analyses showed that the TiO2 nanotubes were coated with ZIF-8 nanoparticles around 50 nm in size. Curves of I-ph vs. E showed that the incorporation of ZIF-8 at Ti/TiO2 electrodes increased the photocurrent and that the values were dramatically increased in solution saturated with CO2. The CO2 adsorbed on the ZIF-8 formed stable carbamates, as demonstrated by spectroscopic and voltammetric assays. Photoelectrocatalytic reduction of CO2 at Ti/TiO2NT-ZIF-8 electrodes resulted in formation of up to 10 mmol L-1 of ethanol and 0.7 mmol L-1 of methanol in 0.1 mol L-1 Na2SO4, at Eapp of +0.1 V, under UV-vis irradiation at room temperature. Our findings open up new applications of metal-organic frameworks (MOFs) in photoelectrocatalysis for the highly efficient preconcentration and conversion of CO2 in aqueous media at ambient temperature. (AU)

• FAPESP's process: 15/18109-4 - Contribution of Nanostructured Materials in Electroanalysis of pharmaceuticals and dyes, in the oxidation and reduction photoeletrocatalytic process of Inorganic and Organic Pollutants and Water Disinfection.
• Grantee: Maria Valnice Boldrin
• Support Opportunities: Regular Research Grants