【摘要】 以压电石英晶体(PQC)技术为基础,研究了光化学方法沉积纳米银粒子到PQC电极表面的过程及机理。将该电极用于检测水中痕量的氰化物,与普通商品PQC的银膜相比,这种新鲜产生的金属纳米银传感层可改善分析性能(检测信号加强3倍)。结果显示该PQC电极频率的变化与氰化物的浓度在0.1~10μmol/L范围内呈线性关系,检出限(2.2μg/L)较世界卫生组织(WHO)对饮用水氰化物含量的指导值低1~2个数量级。详细研究了光化学沉积银过程中的各种影响因素以及检测氰化物过程中的主要影响因素:纳米银粒子的大小及涂层厚度、背景缓冲溶液、pH及样品中共存物质的干扰等。更多还原

【Abstract】 Based on piezoelectric quartz crystal(PQC) technology,the photochemical deposition processes and the mechanism of Ag on TiO2 modified PQC electrode have been studied in detail.The PQC electrode was used for the determination of cyanide at trace levels in water.The freshly produced metallic Ag reacts with cyanide showing improved performance(strengthen the detection signal three times)as comparing to the bulk Ag-coating PQC.The frequencies shifts were measured with results showing a linear relationship within the cyanide concentrations from 0.1-10 μmol/L.The detection limit(2.2 μg/L)was found to be 1-2 orders of magnitude lower than the World Health Organization(WHO) guideline value for drinking water.Effects of various factors including nano-sized silver particle dimension and film thickness,background buffer,solution pH and potential interferents in environmental water samples were investigated.Factors affecting the photo-chemical deposition process of Ag on TiO2 were also studied.更多还原