PMA‐b‐PAA‐controlled synthesis of one‐dimensional CaCO₃ superstructures

Abstract

Key words nano/microwire, CaCO 3 , crystal growth, poly(maleic anhydride)-b-poly(acrylic acid).Crystallization of calcium carbonate (CaCO 3 ) crystals by a gas-liquid diffusion method has been carried out in aqueous solution using a double-hydrophilic block copolymer (DHBC) poly(maleic anhydride)-bpoly(acrylic acid) (PMA-b-PAA). The as-prepared products were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), selected area electron diffraction (SAED), high-resolution transmission electron microscopy (HRTEM) and infrared spectroscopic analysis (FT-IR). Uniform one-dimensional calcite micro/nanostructures with different morphologies are fabricated through an assembled process. The influence of PMA-b-PAA copolymer concentration on the morphology of calcite nano/microwires is investigated, which plays an important role in the morphological control of building blocks composed of one-dimensional calcite crystals. The possible formation mechanism of one-dimensional CaCO 3 crystals was discussed.

Oriented Calcite Micropillars and Prisms Formed through Aggregation and Recrystallization of Poly(Acrylic Acid) Stabilized Nanoparticles

“…Compared with that of PAA, the peak intensity of the CO stretching vibration band at 1680 cm –1 was diminished, and the peak position was shifted to lower wavenumbers in the spectra of both PAA–Ca solids collected from nanofibers and these cloudy solutions, probably due to the strong electrostatic interactions between the carboxylic groups in PAA and Ca 2+ . This is consistent with previously reported results . Thus, we propose that calcium ions first coordinated with PAA, thereby decreasing the calcium ion activity in the CaCl 2 plus PAA solution.…”

“…This is consistent with previously reported results. 43 Thus, we propose that calcium ions first coordinated with PAA, thereby decreasing the calcium ion activity in the CaCl 2 plus PAA solution. This resulted in an undersaturated solution with respect to calcite and, hence, the dissolution of the calcite substrate.…”

“…These structures are reminiscent of calcium carbonate fibers made from a Capolymer precursor. 43 Time dependent observations under conditions adjusted to obtain similar structures in the smallvolume fluid cell of an AFM show that micropillar formation in these conditions is preceded by formation of transient nanoparticles. Moreover, our results show that, with slightly less PAA, the same basic process leads to formation of 3D polyhedral prisms with triangular cross sections in both bulk and AFM experiments.…”

“…Among the variety of morphologies achieved during synthesis of calcium carbonate using the above-mentioned methods, quasi-one-dimensional (1D) calcium carbonate has received a lot of attention and has been successfully synthesized by many research groups through the use of hard templates, , calcite substrates, , polyacid block copolymers, − positively charged additives and microemulsions. , Ward et al synthesized 1D calcite at the millimeter scale by using hierarchical self-assembly of 1D metal–organic protein frameworks as templates . Gower’s group was the first to grow calcite fibers in an aqueous-based system through the PILP process, using a higher molecular weight of polyaspartic acid than is typically used for 3D structures.…”

Leaf‐like copper oxide nanocrystals synthesized by a gas‐liquid diffusion method at room temperature

“…Yu and Colfen have done a series of work to synthesize lots of CaCO 3 and BaCO 3 with special morphologies . You , using gas‐liquid diffusion method, has synthesized one‐dimensional CaCO 3 nano‐micron line with multi‐level structure in the condition of PMA‐b‐PAA‐Na molecules as template. On this basis, some semiconductor metal oxide precursor could also be prepared.…”