Fabrication of coupled twin-shaped hollow hemispherical calcium molybdate via a facile ultrasound-assisted approachElectronic supplementary information (ESI) available: The controlled experiments, characterization explanations and Fig. S1 are presented as ESI. See DOI: 10.1039/c4ce02124j

Coupled twin-shaped hollow hemispherical calcium molybdate (CTHH-CaMoO 4 ) microstructures were successfully synthesized via a facile ultrasound-assisted template-free route in the presence of absolute ethanol and ethylenediaminetetraacetic acid (EDTA). The oriented attachment and subsequent Ostwald ripening mechanism were responsible for the formation of this novel architecture. Coupled twin-shaped hollow hemispherical calcium molybdate (CTHH-CaMoO 4 ) microstructures were successfully synthesized via a facile ultrasound-assisted template-free route in the presence of absolute ethanol and ethylenediaminetetraacetic acid (EDTA).