Amorphous Calcium Carbonate Cluster Nanospheres in Water‐Deficient Organic Solvents
Yi‐Ming Ju, Yang Zhao, Qing‐Fang Guan, Si‐Yao Yang, Wei Wang, Beibei Yan, Yu‐Feng Meng, Sicheng Li, Pei‐Ping Tang, Li‐Bo Mao, Shu‐Hong Yu
Abstract
As the key intermediate phase of crystalline calcium carbonate biominerals, amorphous calcium carbonate (ACC) remains mysterious in its structures because of its long-range disorder and instability. We herein report the synthesis of ACC nanospheres in a water-deficient organic solvent system. The obtained ACC nanospheres are very stable under dry conditions. Cryo-TEM reveals that each nanospheres consists of smaller nanosized clusters. We further demonstrate that these clusters can precipitate on other substrates to form an ultrathin ACC coating, which should be an ACC cluster monolayer. The results demonstrate that the presence of small ACC clusters as the subunits of larger aggregates is inherent to ACC synthesized in water-alcohol system but not induced by polymer additives.