Anisotropic nanowire growth via a self-confined amorphous template process: A reconsideration on the role of amorphous calcium carbonate
amorphous calciumcarbonate, calcite nanowire, anisotropic growth, self-confined amorphoustemplate
Calcium carbonate crystals with various morphologies have been found in avariety of biospecimens and artificially synthesized structures. Usually, thediversity in morphology can be attributed to different types of interactionsbetween the specific crystal faces and the environment or the templates used forthe growth of CaCO3 crystals. On the other hand, isotropic amorphous calciumcarbonate (ACC) has been recognized as the precursor of other crystallinecalcium carbonate forms for both in vivo and in vitro systems. However, here wepropose a self-confined amorphous template process leading to the anisotropicgrowth of single-crystalline calcite nanowires. Initiated by the assembly ofprecipitated nanoparticles, the calcite nanowires grew via the continuousprecipitation of partly crystallized ACC nanodroplets onto their tips. Then, thecrystalline domains in the tip, which were generated from the partly crystallizednanodroplets, coalesced in the interior of the nanowire to form a single-crystallinecore. The ACC domains were left outside and spontaneously formed a protectiveshell to retard the precipitation of CaCO3 onto the side surface of the nanowireand thus guided the highly anisotropic growth of nanowires as a template.
Tsinghua University Press
Li-Bo Mao,Lei Xue,Denis Gebauer,Lei Liu,Xiao-Fang Yu,Yang-Yi Liu,Helmut Cölfen,Shu-Hong Yu, Anisotropic nanowire growth via a self-confined amorphous template process: A reconsideration on the role of amorphous calcium carbonate. NanoRes.2016, 9(5): 1334–1345