Nanocomposites based on Hofmann-type structure Ni^II(pz)[Ni^II(CN)₄] (pz = pyrazine) nanoparticles for reversible iodine capture

Abstract

Hybrid nanocomposites based on nanoparticles with the Hofmann-type structure Ni II (pz)[Ni II (CN) 4 ] (where pz ¼ pyrazine) confined into mesoporous silica or porous glass pearls were synthesised by sequential coordination of the molecular precursors into the pores of the functionalized matrices. Infrared (IR) and UV/Visible (UV-Vis) spectroscopy, powder X-ray diffraction (PXRD), and transmission electron microscopy (TEM) reveal the presence of uniformly-sized spherical Ni II (pz)[Ni II (CN) 4 ] nanoparticles of 3-6 nm, which are homogeneously dispersed into the matrices. These nanocomposites are able to efficiently capture iodine from cyclohexane solutions with a maximum sorption capacity of 1.75 mmol per g of material. A particular emphasis is given on the mechanism of iodine sorption as well as on the sorption cycling ability of the materials.

Aluminum molecular rings bearing amino-polyalcohol for iodine capture

“…S41 and S42 †). 61 To further reveal the trapping mechanism, DFT calculations were undertaken to investigate the electronic structure in AlOC-61 and AlOC-63.…”

Molecular iodine adsorption within Hofmann-type structures M(L)[M′(CN)4] (M = Ni, Co; M′ = Ni, Pd, Pt): impact of their composition

“…The stretching frequency of free iodine in the solid state is at about 180 cm −1 (ν 1 mode) and shifts to lower wavenumbers (around 170 cm −1 ) when iodine interacts with a species that can donate electron density into its σ* antibonding orbital. 43,44 The higher the interaction strength, the lower the force constant and the more the ν 1 mode decreases. In the case of iodide formation, the symmetric and the asymmetric stretching of I 3 − classically appear as strong peaks at 150 cm −1 and 103 cm −1 .…”

Activity of nanostructured C@ETS-10 sorbent for capture of volatile radioactive iodine from gas stream

“…After thermal treatment, 0.59 mass% of I 2 /Zn was observed on cage. Recently, Massasso et al [24] synthesized nanocomposites based Hodmann-type structure of Ni II (pz) [Ni II (CN) 4 ] (pz = pyrazine) into silica or porous glass by sequential coordination of the molecular precursor into the pores of the functionalized matrices. The uniform spherical sized of Ni II (pz) [Ni II (CN) 4 ] in the range of 3-6 nm had a maximum adsorption capacity 1.75 mmol g À1 from cyclohexane solution.…”

“…In recent years, adsorption onto a porous adsorbent has been the primary choice for the removal of radioactive iodine gas due to its advantages that include reliability, simplicity and low operating costs [7]. Previously, several sorbents has been investigated to trap the iodine which includes activated carbon [8,9], silver-exchange zeolite [10], AgNO 3 -impregnated silica and alumina [11,12], silver-functionalized silica aerogels [13], silver-exchanged titania (ETS-10) [14], chalcogen-based aerogel [15][16][17][18], monolithic aerogels of polymeric organic framework [19], and metal organic frameworks [20][21][22][23][24].…”