Morphology and size control of nanocalcium carbonate crystallised in reverse micelle system with cationic surfactant cetyltrimethylammonium bromide

Abstract

The influence of ω 0 , the mole ratio of water-to-surfactant content ([H 2 O]/[surfactant]), on the crystal size of calcium carbonate (CaCO 3 ) produced by reaction crystallisation in microemulsion systems was investigated. Crystallisation was induced by the reaction between an aqueous solution of sodium carbonate and water in oil micellar solutions of calcium chloride stabilised by cationic surfactant cetyltrimethylammonium bromide and cosurfactant n-butylalcohol. The X-ray diffraction results showed that calcite is the main state of CaCO 3 crystal when ω 0 > 30, but because of the stable reverse micelles system, vaterite was the predominant crystal form when ω 0 < 30. Scanning electron microscopy and high-resolution transmission electron microscopy results showed spherical CaCO 3 nanoparticles obtained with narrow size distribution, and with the ratio of water-to-surfactant increasing from 3.40 to 22.63, the particles size increased from 15 to 70 nm. The influence of ω 0 on the crystal size and morphology of CaCO 3 was very clear.

Study on preparation and structure of chrysanthemum‐shaped micron calcium carbonate based on inverse microemulsion

“…According to formula (2), we can calculate the radius of the droplet in the microemulsion, it is . According to the study of Wang Nong's group [16], the size between experimental result and theoretical calculation values according to the CTAB micelle droplet in a microemulsion is different, there is a correction factor k between the experimental value and the theoretical value, which is about k = 10.53 ± 0.56, therefore, the theoretical calculation value in our system is D 1 = 31.98 nm.…”

“…Many research scholars are committed to artificially regulating the morphology and structure of CaCO 3 through various technical means [15]. Among them, the inverse microemulsion method has become one of the research hotspots in recent years [16][17][18][19]. The inverse microemulsion is a water-in-oil dispersion system mainly composed of oil, aqueous, co-surfactants, and surfactants.…”

Study of the influence between magnesium ions and calcium ions on the morphology and size of coprecipitation in microemulsion

“…The coprecipitation of calcium carbonate and Mg 5 (CO 3 ) 4 (OH) 2 •4H 2 O were prepared by the microemulsion of a mixture of CaCl 2 and MgCl 2 . Our previous research has shown that selecting suitable ω 0 values can result in the formation of unique spherical nanoparticles, ω 0 is the mole ratio of water‐to‐surfactant content ([H 2 O]/[surfactant]) [27]. All the microemulsions were prepared at a ω 0 value of 9.0–9.2, the theoretical calculated values of R m (the radius of the droplet) at these ω 0 were calculated according to Kang et al [28] and were about 13 nm.…”

Biomimetic and Bioinspired Synthesis of Nanomaterials/Nanostructures

“…Due to the confined space and unique inducing capacity, reverse micelles and microemulsions are ideal systems for mimicking the formation of various biominerals, and a series of CaCO 3 , silica and phosphate materials have been synthesized. The influence of the synthesis conditions on crystal size, morphology, and structure have been studied in detail.…”