Year: 2025
Type: article
Abstract: Modification of zeolitic structures through the incorporation of transition metal oxides has proven to be a promising approach for heterogeneous catalysis. In the present study, *BEA zeolite was modified using the incipient wetness impregnation method with varying amounts (10, 20, and 40 wt.%) of iron(III) oxide to investigate its structural and physicochemical properties. Characterization techniques such as XRD, UV–Vis DRS, FT–IR, Raman spectroscopy, SEM/EDS, TEM/EDS, and SAED, as well as textural and thermal analyses, were employed to assess the main changes. Different iron species were detected, including isolated iron(III) and well-dispersed Fe2O3 nanoparticles coating the zeolite surface. Under the synthesis conditions, increased Fe2O3 loading promoted hematite nanocrystal growth and the formation of the α-Fe2O3 phase, as demonstrated by XRD, Raman, and SAED analyses. Key observations included the preservation of the zeolite framework, high relative crystallinity (ranging from 70% to 85%), and a band gap of approximately 2.0 eV. Furthermore, a general increase in mesoporosity and external surface area was observed, along with a reduction in the number of acidic sites. This decrease may be attributed to restricted accessibility of the probe molecule (pyridine) to Brønsted sites due to micropore blockage in *BEA. These results demonstrate that the adopted synthesis method effectively produced α-Fe2O3/BEA catalysts, with no other crystalline phases of iron(III) oxide detected.
Source: Inorganics
Institution: Universidade de Brasília
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,654
OpenAlex ID: W4416595297