Fig 1.
Scanning electron microscopy (SEM).
A) Micrographs of cubic NaA zeolite particles, untreated and after ultrasonic treatment, under B) Zn(OH)2, C) ZnO, and D) ZnO2 nanoparticle synthesis and deposition conditions. Insets in all micrographs correspond to their particle size distribution.
Table 1.
Chemical analysis from inductively coupled plasma optical emission spectroscopy (ICP-OES) and energy-dispersive X-ray spectroscopy (EDS).
Fig 2.
Transmission electron microscopy (TEM).
A) Micrographs of NaA, B) Zn(OH)2@NaA, C) ZnO@NaA, and D) ZnO2@NaA, and their corresponding edges E) NaA, F) Zn(OH)2@NaA, G) ZnO@NaA, and H) ZnO2@NaA.
Fig 3.
N2 adsorption-desorption isotherms.
Zeolite NaA (black) modified with Zn(OH)2@NaA (blue line), ZnO@NaA (red line), ZnO2@NaA (green line).
Fig 4.
X-ray diffraction measurements and analysis.
A) Difractograms of zeolite NaA modified with Zn(OH)₂, ZnO, and ZnO₂, and comparison of the observed and simulated intensities from Rietveld refinement indicating the percentage of each Zn phase and zeolite content in the zeolite. B) Differences in the normalized intensity of diffraction peaks between the planes, compared to unmodified NaA and Zn-modified NaA. C) Structural model of NaA showing a cross-section through the (220) plane and D) (440) plane in the NaA structure.
Table 2.
Textural properties measured from the nitrogen adsorption-desorption isotherms.
Table 3.
Displacements of planes relative to NaA, where negative values indicate leftward shifts and positive values indicate rightward shifts.
Fig 5.
Analysis of FT-IR and Raman spectra.
Zeolite NaA A) modified with Zn(OH)2 (blue line), ZnO (red line), and ZnO2 (green line). B) Raman vibration spectra of zeolite B) modified with Zn(OH)2 (blue line), ZnO (red line), and ZnO2 (green line).
Fig 6.
Zeta potential (ζ) measurements.
A) and thermogravimetric analysis (TGA) of NaA B) modified with Zn(OH)2 (blue line), ZnO (red line), or ZnO2 (green line).
Fig 7.
UV-Vis diffuse reflectance spectroscopy deconvoluted spectra.
A) Deconvolution of zeolite NaA, displaying 11 bands that fit the transition state image published by Roberto Nuñez et al. (2023). B) Bands corresponding to NaA (red) and bands corresponding to zinc species (Pink) Zn(OH)2, C) ZnO, and D) ZnO2.
Table 4.
Comparison of conventional and sono-assisted zinc-based nanomaterial synthesis and deposition methods on LTA.