Study of the morphology of copper hydroxynitrate nanoplatelets obtained by controlled double jet precipitation and urea hydrolysis

Abstract

A copper hydroxynitrate of stoichiometry Cu 2 (OH) 3 NO 3 , analogous to the layered double hydroxide family, was synthesized by the so-called controlled double jet precipitation technique, and by hydrolysis of urea in the presence of copper nitrate. Special attention has been focused on the size, morphology and agglomeration tendency of the particles. The aim of this work is to define the optimum precipitation conditions in terms of quality and dispersability of the recovered product. Such platelet-like particles can be used as anisotropic fillers in nanocomposite materials. Several reaction parameters such as flow and concentration of the reactant solutions, design of the reactor and addition of a growth modifier were studied. r

Simple route for the synthesis of copper hydroxy salts

“…The band at 1045 cm -1 corresponds to the N-O stretching vibration of a monodentate O-NO group, which is active in both, FT-IR and Raman spectra (see Figure 4), in good agreement with the literature. 22,26 The shoulder observed at 1375 cm -1 is also assigned to free nitrate ions in the interlamellar space. ).…”

“…As noted, the classical dispersion method employed by Meyn et al 3 and Bruschini and Hudson, 5 using two compounds of the same metal, generates an HS material with a high degree of purity and crystallinity, but has the disadvantage of needing above 24 h of reaction time. Newman and Jones, 4 Henrist et al 8 and Pereira et al 22 reacted copper nitrate with sodium hydroxide using precipitation, dispersion, and co-precipitation methods, respectively, in order to produce a copper HS material. They obtained good results using an elaborated method, by employing the salt at boiling temperature, vacuum conditions and long aging periods, in order to improve the degree of crystallinity of the material.…”

“…The narrow band at 3544 cm -1 corresponds to free OH groups, while the one centered at 3427 cm -1 indicates the presence of hydrogen bonded OH groups. 11,22 The peaks at 1045 (ν 1 ), 800 (ν 2 ), 1343, 1375 and 1426 cm -1 (ν 3 ) can be assigned to vibrational modes of nitrate (NO 3 -) ions, 25 whose interaction with cooper hydroxide layers is evidenced by the appearance of symmetric and asymmetric stretching modes of NO 3 -at 1426 and 1343 cm -1 . The band at 1045 cm -1 corresponds to the N-O stretching vibration of a monodentate O-NO group, which is active in both, FT-IR and Raman spectra (see Figure 4), in good agreement with the literature.…”

“…The peak at 430 cm -1 was assigned to a ν(Cu-O) vibrational mode, while the peak at 876 cm -1 was assigned to Cu-O-H vibrations. 22 Another peak at 1426 cm -1 was attributed to vibrational modes of the nitrate group. A third peak at 1638 cm -1 has been assigned to a bending mode of the hydroxyl group of water.…”

Plasmonic colloidal nanoparticles with open eccentric cavities via acid-induced chemical transformation

“…With increasing irradiation time, the Cu 2 (OH) 3 (NO 3 ) located near the outer surface of spheres was transformed into CuO. Because the volume of a unit cell of monoclinic crystal of Cu 2 (OH) 3 (NO 3 ) is 235 Å 3 , which is larger than that of CuO (81 Å 3 ), 36,37 volume contraction should occur during this transformation from Cu 2 (OH) 3 (NO 3 ) to CuO.…”