Submicrometer-sized, spherical vaterite particles were synthesized by solid-state reaction at room temperature in the presence of poly(acrylic acid)(PAA). The obtained products were characterized by XRD, IR and SEM. I...Submicrometer-sized, spherical vaterite particles were synthesized by solid-state reaction at room temperature in the presence of poly(acrylic acid)(PAA). The obtained products were characterized by XRD, IR and SEM. It was revealed that with increasing PAA amount, the crystal polymorph of CaCO 3 particles varied gradually from pure calcite through a mixture of calcite and vaterite to pure vaterite, and the particle size decreased generally. It was proposed that in solid-state reaction, PAA induced the formation of vaterite and the phase transformation from vaterite to calcite was prevented completely due to the absence of H 2O, resulting in the formation of pure vaterite particles.展开更多
以Na2CO3和Ca Cl2为反应物,分别以一定浓度的聚苯乙烯磺酸钠和L-天冬氨酸为模板通过仿生法和沉淀法合成700 nm^1μm Ca CO3微米球,并通过水热法转化为纳米羟基磷灰石(HA).用XRD、FTIR和TEM等手段对所制得的样品的组成和晶体形貌进行表征...以Na2CO3和Ca Cl2为反应物,分别以一定浓度的聚苯乙烯磺酸钠和L-天冬氨酸为模板通过仿生法和沉淀法合成700 nm^1μm Ca CO3微米球,并通过水热法转化为纳米羟基磷灰石(HA).用XRD、FTIR和TEM等手段对所制得的样品的组成和晶体形貌进行表征,结果表明所合成的Ca CO3为球霰石,在水热条件下,能在短时间内转化为纳米羟基磷灰石,并讨论了转化的可能的机理.展开更多
文摘Submicrometer-sized, spherical vaterite particles were synthesized by solid-state reaction at room temperature in the presence of poly(acrylic acid)(PAA). The obtained products were characterized by XRD, IR and SEM. It was revealed that with increasing PAA amount, the crystal polymorph of CaCO 3 particles varied gradually from pure calcite through a mixture of calcite and vaterite to pure vaterite, and the particle size decreased generally. It was proposed that in solid-state reaction, PAA induced the formation of vaterite and the phase transformation from vaterite to calcite was prevented completely due to the absence of H 2O, resulting in the formation of pure vaterite particles.
