Morphological Stability of Pyrite FeS2 Nanocrystals in Water

By replicating biological processes, it is hoped that many nanomaterials may be tailored for specific applications, but a detailed knowledge of the underlying mechanisms is imperative. A perfect example of this synergy is the similarity between the intracellular biomineralization of single nanocrystals of the nonmagnetic mineral iron pyrite in multicellular magnetotactic bacterium, and the solvo-thermal synthesis of iron sulfide nanoparticles in the laboratory. Although both processes occur in aqueous solutions, the relationship between the morphological stability of the individual nanocrystals and the chemistry of the nanoparticle−water interface is still largely unknown. In the present work, we use a theoretical model capable of describing the stability of nanocrystals as a function of size, shape, temperature, and chemical environment, and use it to examine the morphological stability of pyrite nanocrystals exposed to water, or formed during biomineralization.