posted on 2022-11-18, 00:44authored byCarla Triunfo, Stefanie Gärtner, Chiara Marchini, Simona Fermani, Gabriele Maoloni, Stefano Goffredo, Jaime Gomez Morales, Helmut Cölfen, Giuseppe Falini
Control over the
shape and morphology of single crystals is a theme
of great interest in fundamental science and for technological application.
Many synthetic strategies to achieve this goal are inspired by biomineralization
processes. Indeed, organisms are able to produce crystals with high
fidelity in shape and morphology utilizing macromolecules that act
as modifiers. An alternative strategy can be the recovery of crystals
from biomineralization products, in this case, seashells. In particular,
waste mussel shells from aquaculture are considered. They are mainly
built up of single crystals of calcite fibers and aragonite tablets
forming an outer and an inner layer, respectively. A simple mechanochemical
treatment has been developed to separate and recover these two typologies
of single crystals. The characterization of these single crystals
showed peculiar properties with respect to the calcium carbonate from
quarry or synthesis. We exploited these biomaterials in the water
remediation field using them as substrate adsorbing dyes. We found
that these substrates show a high capability of adsorption for anionic
dye, such as Eosin Y, but a low capability of adsorption for cationic
dyes, such as Blue Methylene. The adsorption was reversible at pH
5.6. This application represents just an example of the potential
use of these biogenic single crystals. We also envision potential
applications as reinforcing fillers and optical devices.