摘要
采用机械粗糙、电化学氧化还原、化学刻蚀等方法对纯钛电极表面进行粗糙,在钛基底上获得了表面增强拉曼光谱(SERS)信号。初步的实验结果表明,采用机械粗糙和电化学氧化还原方法能够获得具有一定粗糙度的电极表面,但是该表面并不具有SERS活性。而采用氢氟酸化学刻蚀方法能够获得具有SERS活性的表面,并且成功检测到吡啶分子的表面增强拉曼信号。实验尝试了在不同条件下进行刻蚀,对酸的刻蚀浓度、刻蚀时间、外接电位等影响因素作了研究,结果发现基底的SERS活性随氢氟酸浓度增大而出现最佳条件,即氢氟酸浓度0.33Wt%,刻蚀时间为5min时的拉曼信号最好。实验以0.01mol·L-1吡啶为探针分子,0.1mol·L-1KCl为电解质,在开路电位下成功地观察了钛电极上的表面增强拉曼光谱。
Various roughening methods for the bare Ti electrode such as mechanical roughening,electrochemical oxidation-reduction method and chemical etching were tried to obtain surface-enhanced Raman spectra（SERS）successfully for the first time.The results of the experiments proved that mechanical roughening and electrochemical oxidation-reduction method could be successfully employed in roughening titanium electrode,however,surfaces roughened in such ways showed no SERS-activity in Raman detection.Finally,chemical etching with hydrofluoric acid was proved to be an effective way to get SERS-active titanium surface,and surface-enhanced Raman spectra of pyridine adsorbed on a titanium surface was observed for the first time.In order to get the most effective titanium surface,roughening conditions,including concentration of the acid,the time of etching and the external potential,were investigated.As illustrated,Raman activity varies with conditions changing in roughening processes and the most reasonable condition for roughening was indicated.The result showed that at the concentration of hydrofluoric acid 0.33%（Wt）and 5 min for etching,the most SERS-active rough titanium surface could be obtained.In addition,with an external potential to speed up corrosion,the surface of titanium electrode tended to form a thin film of oxide,which prevented further corrosion and caused SERS-activity decrease.Thus,in this paper,the surface-enhanced Raman spectra of pyridine（pyridine 0.01 mol·L-1,and electrolyte KCl 0.1 mol·L-1）adsorbed on bare roughed Ti electrode were observed at open circuit potential.Referring to the calculations of enhancement factor of pyridine on electrode,the enhancement factor is about 102 on the roughened titanium electrode.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2009年第12期3300-3303,共4页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(20573076
20503019
20773091)
教育部高等学校博士点基金项目(20050285019)
江苏省自然科学基金项目(BK2005032)资助
关键词
钛电极
表面增强拉曼光谱
吡啶
粗糙方法
Titanium electrode Surface-enhanced Raman spectroscopy（SERS） Pyridine Roughening method
