Cathodrochromic Properties of Sodalite

Abstract

The coloration and bleaching behavior of undoped bromide sodalite prepared by solid-state reaction and by various low-temperature hydrothermal reactions is studied. A high coloration sensitivity is obtained; for instance, a charge density of 0.5 μC/cm2 at 10 kV yields a contrast ratio of 2:1. The coloration and optical bleaching behavior is strongly dependent on the preparation method. A relation between bleaching rate and bromide deficit is found. A relation is suggested between residual coloration and the presence of oxygen on bromine sites. The effect of the doping with transition-metal ions on the bleaching behavior is studied. The doping with Fe, Ni, and Cu causes a considerable increase in bleaching rate.

Isomorphous gallium substitution in the alumosilicate sodalite framework: synthesis and structural studies of chloride and bromide containing phases

“…The low residual values in almost all refinements indicate a good quality of fit as well as single phase sodalite as a preliminary consideration. The starting crystal parameters were taken from the structure reports of Na 8 [37] for the re- At an early stage of the refinement, a gallium atom was set on the silicon site (6d) summing the total population constrained to 1.0. After a few cycles of refinement, the occupancy factor of the gallium atom on the silicon site converged to 0.00 AE 0.02 suggesting that the 6d sites are fully occupied only by silicon atoms.…”

“…In some recent conference contributions [29][30][31][32] we reported for the first time several partially T-site substituted alumogallosilicate sodalites along with their respective parent end members. Following those contributions we present here a series of alumogallosilicate halide sodalites, Na 8 [Al 1Ày Ga y SiO 4 ] 6 Y 2 , where 0 y 1 and Y ¼ Cl/Br. We will explore how the trivalent aluminium occupancy in the sodalite framework can be controlled by the systematic substitution with lager gallium atoms under hydrothermal synthesis conditions.…”

“…Sodalites, therefore, have been regarded as a model compound to study the discrete b-cage effects on intra-zeolite chemistry for larger and complicated zeolites. Besides, sodalites are interesting for diverse pro-chromic behaviours (barochromic, hydrochromic, photochromic, cathodochromic) [5][6][7][8], ion exchange character [9][10][11] and discrete microcluster (Na 4 3þ ) studies [12,13]. Ozin et al [5] proposed that by controlled loading of the trapped species it is possible to form cluster and extended supercluster structures in the quantum size regime, similar to semiconductor superstructures.…”

“…Ozin et al [5] proposed that by controlled loading of the trapped species it is possible to form cluster and extended supercluster structures in the quantum size regime, similar to semiconductor superstructures. Most of those studies [5][6][7][8][9][10][11][12][13] are directly correlated to the effective pore dimension of the six-ring windows of the bcage, which can substantially be modified by isomorphous substitution. Most of the previous works, concerning substitution, were on a topotactic manipulation of the guest species [14][15][16][17][18] or on a complete replacement [14,[19][20][21] of the framework T-atoms.…”

Synthesis, Characterization and Crystal Structure of Gallosilicate Perchlorate Sodalite

“…Depending on the composition sodalite posses photochromic, cathodochromic, ion conducting properties and as high density optical data storage materials. Sodalites with special guest anion can be used for various technical applications like pigments, ultramarine, graphical and digital storage system, luminescence and catalytic activity (Hassan et al, 1984;Schipper et al, 1972;Van Doorn et al, 1972;Mclaughan et al, 1970;Bolwijn et al, 1972;Chang, 1974 (Piontkovskaya et al, 1970, Suzuki et al, 1985, McCusker et al, 1986, Newsam et al, 1987, Bu, Xianhui et al, 1998Gesing et al, 2000, Buhl et al, 2006, Murshed et al, 2007 Sodalites are expected to be an interesting model system for studying simple principle of perchlorate storage in small cavities of framework structure (Weitkamp et al, 1995), we extend our experimental work here on synthesis, characterization and structure of perchlorate encapsulated sodalite with gallosilicate framework. Substitution of framework by gallium is of special interest to study interactions of encapsulated ClO 4 -guest anion with a host framework of certain composition.…”