000063138 001__ 63138
000063138 005__ 20191122145054.0
000063138 0247_ $$2doi$$a10.1039/c7dt03718j
000063138 0248_ $$2sideral$$a101791
000063138 037__ $$aART-2018-101791
000063138 041__ $$aeng
000063138 100__ $$aRoth, W.J.
000063138 245__ $$aPillaring of layered zeolite precursors with ferrierite topology leading to unusual molecular sieves on the micro/mesoporous border
000063138 260__ $$c2018
000063138 5060_ $$aAccess copy available to the general public$$fUnrestricted
000063138 5203_ $$aLayered zeolite materials with FER layer topology can produce various condensed and expanded structures including zeolite frameworks, FER and CDO, their interlayer expanded forms (IEZ), and organic-intercalated and pillared derivatives. This work concerns pillaring of the surfactant-swollen derivative with a gallery height of ca. 2.5 nm between layers by treatment with tetraethylorthosilicate (TEOS) at room and elevated temperatures. The materials obtained at 100 °C and higher showed unusual properties including 2 nm pores on the micro/mesoporous border and disordered layer packing indicated by the absence of distinct low angle interlayer peaks at d-spacing >3 nm (~3° 2¿ Cu Ka radiation) in the X-ray diffraction pattern (XRD). TEOS treatment at room temperature produced a pillared molecular sieve with the expected mesoporous characteristics, namely a pore size of around 3 nm and a high intensity low angle (001) peak at 2.3° 2¿, and a d-spacing of 3.8 nm, in the XRD. The characterization aiming to elucidate the nature of the obtained unusual products included gas adsorption isotherms, aberration corrected (Cs-corrected) Scanning Transmission Electron Microscopy (STEM) studies and 29Si solid state NMR. BET surface area values decreased with the temperature of TEOS treatment from approximately 1200 m2 g-1 to ~900 and 600 m2 g-1, at room temperature, 100 °C, and 120 °C, respectively. The 29Si solid state NMR revealed the presence of both Q3 ((SiO)3SiOX, X = H or minus charge) and Q4 ((SiO)4Si) centers giving separated signals up to the pillaring step. After pillaring at 100 °C and calcination, the nominal intensity ratios Q4:Q3 were 2.17 and 2.61 but the signals were merged into one broad peak indicating the structural heterogeneity of Si-O coordination. The microscopy showed the presence of FER layers in the samples but the overall structure and composition were not well-defined. The observed unusual disorganization and possible partial degradation of layers during pillaring may result from the combination of high temperature, alkalinity (surfactant hydroxide) and siliceous composition of the layers. The obtained pillared products are of interest for the preparation of larger pore catalysts and sorbents or controlled drug delivery.
000063138 540__ $$9info:eu-repo/semantics/openAccess$$aby-nc-nd$$uhttp://creativecommons.org/licenses/by-nc-nd/3.0/es/
000063138 590__ $$a4.052$$b2018
000063138 591__ $$aCHEMISTRY, INORGANIC & NUCLEAR$$b7 / 45 = 0.156$$c2018$$dQ1$$eT1
000063138 592__ $$a1.12$$b2018
000063138 593__ $$aInorganic Chemistry$$c2018$$dQ1
000063138 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/submittedVersion
000063138 700__ $$aGil, B.
000063138 700__ $$0(orcid)0000-0002-5229-2717$$aMayoral, A.
000063138 700__ $$aGrzybek, J.
000063138 700__ $$aKorzeniowska, A.
000063138 700__ $$aKubu, M.
000063138 700__ $$aMakowski, W.
000063138 700__ $$aCejka, J.
000063138 700__ $$aOlejniczak, Z.
000063138 700__ $$aMazur, M.
000063138 773__ $$g47, 9 (2018), 3029-3037$$pDalton Trans.$$tDalton Transactions$$x1477-9226
000063138 8564_ $$s1731945$$uhttps://zaguan.unizar.es/record/63138/files/texto_completo.pdf$$yPreprint
000063138 8564_ $$s57301$$uhttps://zaguan.unizar.es/record/63138/files/texto_completo.jpg?subformat=icon$$xicon$$yPreprint
000063138 909CO $$ooai:zaguan.unizar.es:63138$$particulos$$pdriver
000063138 951__ $$a2019-11-22-14:44:37
000063138 980__ $$aARTICLE