热丝化学气相沉积法制备钛基 BDD 电极及苯酚降解性能研究

目的研究硼掺杂对改善金刚石膜的电阻率的影响,制备掺硼金刚石膜。方法采用热丝化学气相沉积系统,以CH4,H2,(CH3O)3B混合气体为反应气,在钛片衬底上沉积制备掺硼金刚石膜电极。对不同生长阶段沉积出的电极进行扫描电镜、EDX光电子能谱、激光Raman光谱、X射线衍射、电化学性能表征及废水降解应用研究。结果制备出的掺硼金刚石膜呈现出均匀的(111)晶面,Raman光谱图中金刚石特征峰与硼原子特征峰峰型显著,具有较低的背景电流和更宽的电位窗口(3.5 V),对苯酚废水COD降解效果显著。结论有机污染物的吸附量与电极表面的粗糙度正相关,实验室制备的BDD/Ti电极表面粗糙度小,不利于析氢和析氧等副反应的发生,能降低直接电化学氧化作用,从而得到更宽的电势窗口。

Preparation of BDD/ Ti Electrode by HFCVD Method and Its Performance in Phenol Degradation

Objective To study the effect of boron doping on the improvement of the resistivity of diamond film, and to prepare boron doped diamond film. Methods The hot-filament chemical vapor deposition (HFCVD) system was chosen for the preparation of Boron doped diamond (BDD) film on the Ti substrate, with the H2, CH4 and (CH3O)3B mixture as the reaction gas. SEM, EDX, Raman spectra, XRD and electrochemical workstation were used for the morphology and electrochemical detection of BDD film in different growth stage. Results The BDD film displayed uniform (111) crystal face, and obvious characteristic peaks of diamond atom and boron atom were found through Raman spectra. The background currents were low and the potential window was wider (3. 5 V). The COD degradation of phenol wastewater was remarkable. Conclusion The adsorption of organic pollutants was positively correlated with the roughness of the electrode surface. The laboratory prepared BDD / Ti electrode had smaller surface roughness, which was not favorable for the occurrence of hydrogen evolution and oxygen evolution, and could reduce the direct electrochemical oxidation, resulting in a wider potential window.