Photolysis of 1-pyrenemethylamine ion-exchanged into a zirconium phosphate framework

Effect of Synthesis Conditions on Formation of Thermally Stable Mesoporous Zirconium Phosphate

“…Zirconium phosphate is also quite resistant to acids, except for HF, H 2 SO 4 , and H 2 C 2 O 4 , which form complexes with zirconium. Furthermore, zirconium phosphates and its modified forms, along with metal oxides, zeolites, molecular sieves, activated carbons, and other porous materials, are widely used as catalyst supports and catalysts in isomerization reactions [1], Friedel-Crafts acylation using benzyl chloride [2], and also as a matrix for controlled assembly of semiconductor clusters and organic molecules [3,4]. These materials can be used in nonlinear optics, in electronic and optical processes [5], and also as proton conductors in proton exchange membranes in fuel cells for direct conversion of chemical energy to electrical energy [6].…”

“…zirconium phosphate formation can be represented as gradual substitution of water molecules by PO 4 3-groups in the inner sphere of Zr 4+ . The rate of this process decreases as each subsequent water molecule is substituted [9].…”

“…After hydrothermal treatment, the precipitates were filtered out, washed with distilled water, dried at 100°C; then all three parts were detemplated by raising the temperature at heating rate 2°C/min up to 500°C, and held at that temperature for 5 h. We used a similar procedure to synthesize zirconium phosphate with other templates (cetylpyridinium chloride (CPCl), sodium dodecyl sulfate (DDSN), dodecylbenzenesulfonic acid (DDBSC), and a triblock copolymer (Pluronic P123), and also dodecylamine (DDA) and octylamine (OA)). The composition of the reaction mixture (in moles) was: 0.01Zr 4+ : 0.019PO 4 3-: 0.0069Surfactant : 5.5H 2 O, pH 1.8.…”

“…Formation of different types of structures is probably connected with the state of the zirconium ions in solution, which in turn depends on the acidity of the medium, the concentration of zirconium and the anions of the acids or salts of zirconium, capable of complexation with zirconium ions [17,18]. The first two factors determine the degree of hydrolytic polymerization of zirconium; the third factor (the presence of F -, Cl -, SO 4 2-in the reaction mixture) affects mainly the distribution of zirconium between cationic, neutral, and anionic forms [19]. Precipitation of zirconium phosphate occurs from an acidic medium (pH 1-2) [14], which becomes possible due to the greater complexing ability of phosphate ions compared with sulfate ions (50% and 32% respectively [15] [20].…”

“…In zirconyl chloride solutions, Zr is present in the form of tetrameric complexes, which can then enter into a polymerization reaction, and according to [19] the electrically neutral complexes predominate. The complexing ability of the inorganic ligands relative to zirconium corresponds to the series F -> PO 4 3-> SO 4 2-> Cl - [17]. Considering that fluoride ions have high complexing ability relative to zirconium, often HF is added to the retion mixture and as a result the complexes [ZrOF 4 ] 2-and/or [ZrF 6 ] 2-are formed [14].…”