Polyacids for producing colloidally stable amorphous calcium carbonate clusters in water

As an important precursor of crystalline phases, amorphous calcium carbonate (ACC), especially ultrasmall ACC clusters, have been attracting great interest in fundamental research, materials chemistry, as well as industrial applications. However, it is still challenging to synthesize stable ACC clusters in water that can be isolated and concentrated without severe aggregation. Herein, we report a facile dialysis method for producing colloidally stable ACC clusters that are well dispersed in water with the protection of specific polycarboxylic acids, which could be also easily deprotected by small-molecule acids like sodium citrate. Inherent proto-calcite short-range order is found to be present in all the obtained ACC clusters. The present strategy not only allows for the preparation of monodisperse isolated ACC clusters in aqueous solution but also shows great potential in industrial uses like waste water treatment.

Automated summary

A facile dialysis method for producing stable ACC clusters in water has been reported in this study, showing the potential for industrial uses like waste water treatment. The obtained ACC clusters exhibit inherent proto-calcite short-range order.