. It was carried out
using a JEOL-JSM6700F at 15 kV. The crystalline phase and structure
of the synthesized CaCO3 were detected by X-ray diffraction (XRD)
analysis with a Shimadju D/max-rA X-ray diffractometer with Cu Kα
radiation, under the accelerating voltage 40 kV, current 30 mA, and
scanning rate 4° min−1. The contact angle was measured at 25 °C with
a FTÅ200 (USA) contact angle analyzer. On flat solid surfaces, the
contact angle could be measured by the sessile drop technique. The
powdery samples (1 g) in 10 MPa pressure were first pressed into
thin pellet and then the water droplet was dropped onto the pellet.
The contact angle against water on a horizontal surface of a pellet was
obtained. Fourier transforminfrared spectroscopy (FT-IR)was performed
on an Ominic System 2000 using KBr pellets. The thermogravimetry
analysis (TGA) was performed on Melttler Toledo 825e instrument at
50–900 °C with a program heating rate of 10 °C min−1 in a flowing air
atmosphere.