Fabrication Of The Prismatic-type CaCO₃ Thin Films Via Seeded Mineralization And Their Applications

Compared to natural minerals,biominerals often possess multiple remarkable structural functions,such as fracture toughness and wettability.This can be largely attributed to the presence of complex hierarchical architectures and their structural uniformity across the macroscopic distance controlled by biomacromolecules.Therefore,the study of biomimetic mineralization can help us understand the mineralization mechanism of biominerals,and provide new methods for the fabrication of new multifunctional materials.The nacre and prismatic layers found in the mollusk shell are the two most studied models in the current biomimetic mineralization work because of the simple micro-structures and excellent mechanical properties.For the nacre structure,people have successfully simulated the nacreous structure in various ways,which possessing excellent mechanical properties.While for the prismatic layer,the existing researches are mostly based on the mineralization on the surface of polymers,self-assembled films and some natural minerals.However,due to the restriction of the surface nucleation number density,these methods are difficult to obtain highly oriented and macroscopic continuous prismatic-type CaCO3 thin films.Based on the current research,in this paper,we provide a new mineralization method to fabricate macroscopic continuous,prismatic-type CaCO3 thin film based on the epitaxial growth of seed layer.First,a seed layer granular in nature was deposited on the polymer substrate,and then epitaxial growth of the CaCO3 was achieved on the seed layer,leading to a uniform prismatic-type CaCO3 thin film.The exist of the seed layer can effectively increase the nucleation density during the epitaxial growth,thus providing a basis for the mineralization of continuous CaCO3 film.By adding different polymer additives in the mineralization process,the microstructures of the CaCO3 film can be effectively regulated.The appearance of micro-nano structures can lead to specific structural functions,such as underwater superoleophobicity,ultralow adhesion force and excellent mechanical properties.In addition,this method can also be extended to mineralization on curved substrates.The nylon mesh after mineralization can be used for oil-water separation,and has excellent separation effect.In general,this paper provides an economical and effective seed-based biomimetic mineralization method.The seeded mineralization provides a good platform for other biomimetic mineralization research.Moreover,this method is universal,which can be applied to the f'abrication of other new multifunctional organic-inorganic composite materials.