Nonionic surfactant-assisted strategy towards disorderly layered UiO-66-on-clinoptilolites heterostructure as efficient adsorbent for selective adsorption of CO2 and CH4

Abstract

• Nonionic surfactant-assisted strategy for UiO-66-on-clinoptilolite was proposed. • MOF particle located on facet exposures of CP lamellas was controlled by PEG and PVP. • UiO-66-NH 2 -on-CP hybrid exhibited an excellent separation performance for CO 2 and CH 4. The constructed strategy of the disorderly layered UiO-66-on-clinoptilolite heterostructures was proposed through assistance of polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP). Their physicochemical properties were demonstrated via various characterizations, such as X-ray powder diffraction (XRD) patterns and scanning/transmission electron microscope (SEM/TEM) images. Particularly, the small‑angle X‑ray scattering (SAXS) method was employed to elucidate their fractal structure evolutions, manifesting the transformations of surface fractal with irregularity and roughness. The results showed that the PEG introduction was beneficial to the formation of disorderly layered clinoptilolites (CP). The particles sizes of UiO-66-NH 2 were successfully controlled via additive PVP, and the interactions between UiO-66-NH 2 and deposited CP-PEG were enhanced. The preliminarily adsorption performances of the obtained UiO-66-on-CPs exhibited a superior selective factor (around 26) of CO 2 /CH 4 . This approach may open a new avenue to improve its adsorption selective performance for CO 2 and CH 4 due to its dual microporous features and enlarged lamellar spacing.