Abstract The mechanisms by which amorphous intermediates transform into crystalline materials are poorly understood. Currently, attracting enormous interest is the crystallization of calcium carbonate, a key intermediary in synthetic, biological and environmental systems. Here we attempt to unify many contrasting apparently contradictory studies investigating this process detail. We show that carbonate can dehydrate before crystallizing, both solution air, while thermal analyses solid-state...

Structuring over many length scales is a design strategy widely used in Nature to create materials with unique functional properties. We here present comprehensive analysis of an adult sea urchin spine, and revealing complex, hierarchical structure, show how fabricates material which diffracts as single crystal calcite yet fractures glassy material. Each spine comprises highly oriented array Mg-calcite nanocrystals amorphous regions macromolecules are embedded. It postulated that this...

This work investigates the early stages of precipitation calcium sulfate from aqueous solution at room temperature and shows for first time that amorphous (ACS) hemihydrate are sequentially precipitated prior to dihydrate (gypsum).

Abstract The term mesocrystal has been widely used to describe crystals that form by oriented assembly, and exhibit nanoparticle substructures. Using calcite co-precipitated with polymers as a suitable test case, this article looks critically at the concept of mesocrystals. Here we demonstrate data commonly assign structure may be frequently misinterpreted, these calcite/polymer do not have Although morphologies suggest presence nanoparticles, are only present on crystal surface. High...

Abstract Soluble macromolecules are essential to Nature's control over biomineral formation. Following early studies where rich in aspartic and glutamic acid were extracted from nacre, research has focused on the use of negatively charged additives calcium carbonate precipitation. It is demonstrated that positively additive poly(allylamine hydrochloride) (PAH) can also cause dramatic changes calcite morphologies, yielding thin films fibers CaCO 3 analogous those produced with poly(aspartic...

Calcite single crystals containing polystyrene particles are synthesized using a straightforward, one-pot method, through control of the particle surface structure and crystallization conditions. Investigation mechanical behavior these composite nanoindentation shows enhanced fracture toughness via crack bridging mechanism. Detailed facts importance to specialist readers published as "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They made available...

Abstract Manipulation of inorganic materials with organic macromolecules enables organisms to create biominerals such as bones and seashells, where occlusion biomacromolecules within individual crystals generates superior mechanical properties. Current understanding this process largely comes from studying the entrapment micron-size particles in cooling melts. Here, by investigating micelle incorporation calcite atomic force microscopy micromechanical simulations, we show that different...

Abstract Amorphous calcium carbonate (ACC) is an important intermediate in the formation of crystalline CaCO 3 biominerals, where its crystallization controlled using soluble additives. However, although this transformation often occurs solid state, experiments mainly focus on effect additives ACC solution. This paper addresses issue and compares crystallization, solution precipitated presence a range Surprisingly, these results show that some exhibit Janus behavior, they retard solution,...

Our understanding of crystal nucleation is a limiting factor in many fields, not least the atmospheric sciences. It was recently found that feldspar, component airborne desert dust, plays dominant role triggering ice formation clouds, but origin this effect unclear. By investigating structure/property relationships wide range feldspars, we demonstrate alkali feldspars with certain microtextures, related to phase separation into Na and K-rich regions, show exceptional ice-nucleating abilities...

In this work, we studied the heterogeneous nucleation and growth of CaCO3 within regular arrays picoliter droplets created on patterned self-assembled monolayers (SAMs). The SAMs provide well-defined substrates that offer control over nucleation, used these impurity-free droplet to study crystal in spatially chemically controlled, finite-reservoir environments. results demonstrate a number remarkable features precipitation confined volumes. crystallization proceeds significantly more slowly...

Single-crystal calcite nanowires are formed by crystallization of morphologically equivalent amorphous calcium carbonate (ACC) particles within the pores track etch membranes. The polyaspartic acid stabilized ACC is drawn into membrane capillary action, and single-crystal nature attributed to limited contact intramembrane particle with bulk solution. reaction environment then supports transformation a product. Detailed facts importance specialist readers published as "Supporting...

While negatively charged organic additives are widely used as an effective means to control CaCO3 precipitation, positively generally considered be much less active. Nevertheless, the cationic polyelectrolyte poly(allylamine hydrochloride) has recently been shown exert significant over driving formation of thin films and fibers, other examples suggest that many promote vaterite formation. This article aims bring together these sometimes conflicting views activity additives. The effect a...

A facile one-pot method is described for the formation of novel heterostructures in which inorganic nanoparticles are homogeneously distributed throughout an single crystal matrix. Our strategy uses functionalised with a poly(sodium 4-styrenesulphonate)-poly(methacrylic acid) [PNaStS-PMAA] diblock copolymer as soluble growth additive. This plays number essential roles. The PMAA anchor block physically adsorbed onto nanoparticles, while PNaStS acts electrosteric stabiliser and ensures that...

Significance Calcium carbonate is a widespread compound whose two common crystalline forms, calcite and aragonite, are important biominerals. Although aragonite only marginally less stable than under ambient conditions, it usually crystallizes from solution at high temperatures or in the presence of magnesium ions. However, organisms readily form both biominerals, capacity attributed to action specific organic macromolecules. By investigating calcium precipitation submicron pores we here...

This article describes an experimentally versatile strategy for producing inorganic/organic nanocomposites, with control over the microstructure at nano‐ and mesoscales. Taking inspiration from biominerals, CaCO 3 is coprecipitated anionic diblock copolymer worms or vesicles to produce single crystals of calcite occluding a high density organic component. approach can also be extended generate complex structures in which are internally patterned nano‐objects differing morphologies. Extensive...

Abstract Acidic macromolecules are traditionally considered key to calcium carbonate biomineralisation and have long been first choice in the bio-inspired synthesis of crystalline materials. Here, we challenge this view demonstrate that low-charge can vastly outperform their acidic counterparts nanocomposites. Using gold nanoparticles functionalised with low charge, hydroxyl-rich proteins homopolymers as growth additives, show extremely high concentrations be incorporated within calcite...

The biomimetic synthesis of patterned mineral thin films, based on a combination the microcontact printing technique and novel crystallization process called polymer-induced liquid-precursor (PILP) process, is demonstrated. PILP enables deposition smooth continuous calcitic films (up to 1500 nm in thickness) under low-temperature aqueous-based processing conditions. are formed by colloidal droplets composed liquid-phase precursor that induced polymeric process-directing agent (polyaspartate...

Inspired by the observation that crystalline calcium carbonate and phosphate biominerals frequently form via amorphous precursors, a wide range of studies have been performed which demonstrate many inorganic crystals can precipitate from solution phases. This article considers crystallization mechanism oxalate, is significant biomineral in plants primary constituent kidney stones vertebrates, shows this also an precursor phase aqueous solution. A approaches were employed to study oxalate...

Abstract As crystallization processes are often rapid, it can be difficult to monitor their growth mechanisms. In this study, we made use of the fact that proceeds more slowly in small volumes than bulk solution investigate effects soluble additives Mg 2+ and poly(styrene sulfonate) (PSS) on early stages calcite crystals. Using a “Crystal Hotel” microfluidic device provide well‐defined, nanoliter volumes, observed crystals form via an amorphous precursor phase. Surprisingly, first formed...

Abstract Most of our knowledge dislocation-mediated stress relaxation during epitaxial crystal growth comes from the study inorganic heterostructures. Here we use Bragg coherent diffraction imaging to investigate a contrasting system, calcite (CaCO 3 ) crystals on organic self-assembled monolayers, where these are widely used as model for biomineralization processes. The imaged simultaneously visualize morphology and internal strain fields. Our data reveal that each possesses single...

Abstract Amorphous calcium carbonate (ACC) is a common precursor to crystalline carbonate, and of particular importance in biomineralization, where its crystallization privileged environments ensures pseudomorphic transformation. While organisms regulate this process using organic molecules magnesium ions selectively form calcite or aragonite, it has proven highly challenging replicate polymorph selectivity synthetically. Here, demonstrated that remarkable control can be achieved over the...