表面增强拉曼技术监测Au-BiOCl-OV光催化氧化苯甲醇

Monitoring Au-Bi OCl-OV photocatalytic oxidation of benzyl alcohol by surface-enhanced Raman technique

通过高压釜加热、氧气(O_(2))氛围内煅烧的方式制得具有氧空位(OVs)的氯化氧铋(BiOCl-OV),然后将水热法制备的金纳米粒子(Au NPs)偶联在其表面,构建既具有表面增强拉曼活性又有光催化活性的等离子催化剂(Au-BiOCl-OV).通过拉曼光谱、场发射扫描电子显微镜(FE-SEM)、元素组成分析和X射线光电子能谱(XPS)对该复合材料进行了表征,并通过拉曼光谱研究了其对苯甲醇的光催化氧化作用.研究发现:在紫外光照射下,该材料可以有效催化苯甲醇转化为苯甲醛,在拉曼光谱1 700 cm^(-1)处出现归属于C=O面内拉伸振动的特征峰,且峰强比(I_(1 700)/I_(1 000))随光照时间的延长而增大,两者呈良好的线性关系.实验结果表明:该等离子体催化剂不仅光催化活性高,且结合拉曼光谱可以直接对光催化过程进行监测.

Bismuth oxychloride with oxygen vacancy (BiOCl-OV) was prepared by autoclave heating and calcination in an oxygen(O_(2)) atmosphere.Then,the hydrothermally prepared gold nanoparticles (Au NPs) were coupled on its surface to construct plasmonic catalysts (Au-BiOCl-OV) with surface-enhanced Raman and photocatalytic activity.The composites were characterized by Raman,field emission scanning electron microscope(FE-SEM),elemental composition analysis,and X-ray photoelectron spectroscopy(XPS).The oxidation of benzyl alcohol catalyzed by the composite was investigated by Raman spectroscopy.The study suggests that under UV light irradiation,the composite can effectively catalyze the conversion of benzyl alcohol to benzaldehyde.The chartereristic peak at 1 700 cm^(-1) in the SERS spectrum is attributed to the C=O in-plane stretching vibration.The peak intensity ratio(I1 700/I1 000) increases with the prolongation of illumination time,showing a good linear relationship between I1 700/I1 000and illumination time.