添加双氧水阴极沉积羟基磷灰石的研究

通过Tafel曲线,在不同的体系中考察了双氧水对钛电极的影响:Cl、NO-3体系对钛腐蚀电位的影响很小,在有Ca2 和P存在下,不含双氧水的体系的腐蚀电位要更负;通过X射线和SEM扫描电镜发现,随着双氧水浓度的提高,羟基磷灰石衍射峰的强度增强,基体钛的衍射峰减弱;H2O2用量较高时(浓度达到9%),其衍射峰变得更加尖锐,说明羟基磷灰石的结晶度得到了提高.在H2O2用量浓度较低时,其晶体形貌为团絮状结构,随着浓度的增加,生成的OH-增多,晶体形状变为大片状,相互交错形成具有较大孔洞的网状结构,膜也变得致密.但是,不管双氧水浓度如何变化,沉积过程中由于不导电的涂层不断生长,使得电极表面电阻增大,造成阴极电流密度总体趋向都是不断减小.

Study on the Process of Hydrogen Peroxide of HAP Cathode Electrodeposition

The effects of different systems on titanium electrode are studied by Tafel curves in this paper. The systems of Cl~-,NO~-_3 have little effect on it. Corrosion potential in the system with H_2O_2 is more negative when Ca~ 2+ and P exist.With X-radial and SEM, it is shown that the intensity of diffraction apices of HAP increases while that of titanium decreases with the elevation of the concentration of H_2O_2. The more the dosage of H_2O_2, the more speculate diffraction apices of HAP become.This shows that crystal degree of HAP improves. If the concentration of H_2O_2 is slow, its crystal is garrulous framework. With the more H_2O_2 and more produced OH~-, its crystal becomes big flake. It intervens each other to form reticulation system with big hole and its film becomes dense. However, due to the insulated coatings develop perpetually to make high resistance on the surface of electrode, no matter how the concentration of HAP changes, the tendency of cathode current density decreases incessantly in the total.