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Computational elucidation of the aging time effect on zeolite synthesis selectivity in the presence of water and diquaternary ammonium iodide
, Article Physical Chemistry Chemical Physics ; Volume 23, Issue 37 , 2021 , Pages 21240-21248 ; 14639076 (ISSN) ; Kazemi Zangeneh, F ; Sastre, G ; Moeinian, M ; Marhabaie, S ; Taheri Rizi, Z ; Sharif University of Technology
Royal Society of Chemistry
2021
Abstract
An example of zeolite selectivity (MFI → MOR) driven by synthesis aging time has been studied. Using N,N,N′,N′-tetramethyl-N,N′-dipropyl-ethylenediammonium diiodide (TMDP) as an organic structure-directing agent (OSDA), the zeolite phases obtained at 2 h (MFI 97%), 8 h (MFI 84%, MOR 16%) and 24 h (MFI 43%, MOR 57%) have been characterized by powder X-ray diffraction. The results suggest that at intermediate aging time, namely 8 h and 24 h, the dominant phase (MFI) is displaced by MOR. Different techniques (FT-IR, Raman, 13C MAS NMR, TGA/DTG and HC microanalysis) have been employed to verify the OSDA integrity and occlusion inside the zeolite micropores as well as to quantify the water and...
Synthesis of mesoporous TiO2 structures through P123 copolymer as the structural directing agent and assessment of their performance in dye-sensitized solar cells
, Article Solar Energy ; Volume 133 , 2016 , Pages 24-34 ; 0038092X (ISSN) ; Mozaffari, N ; Sharif University of Technology
Elsevier Ltd
Abstract
A novel and efficacious strategy was implemented for creation of mesoporous TiO2 films and powder through an integration of sol-gel and evaporation-induced self-assembly (EISA) processes aided by triblock Pluronic P123. A mesoporous crack-free thin film with virtual thickness of 300 nm was attained under 10% relative humidity aging, for 72 h at the low temperature of 5 °C. Further, the TiO2 film with porous structure has been formed from conventional paste, exploiting as-prepared mesoporous titania powder. The X-ray Diffraction (XRD) of synthesized mesoporous powder disclosed formation of anatase phase as well as rutile phase, in such a manner that the latter constituted a very small...