利用壳聚糖的吸附性能和石墨相氮化碳的光催化特性制备了g-C₃N₄/壳聚糖复合微球,并对银离子进行吸附还原,将所得产物应用于表面增强拉曼(SERS)基底来检测孔雀石绿(MG)。结果表明,制备的复合微球对银离子有较好的吸附容量,可达到152.17 mg/g,吸附银离子后的微球对孔雀石绿的吸附能力降至2%。SERS图谱的特征峰较易分辨,对MG的检测范围为1×10^-7~1×10^-3 mol/L,但复合微球对孔雀石绿的降解能力会影响其长时间的拉曼检测。扫描电镜与能谱分析结果表明,复合微球表面较粗糙,有纳米银生成,分布较为均匀。XPS分析结果表明,复合微球表面主要为单质银。红外光谱分析表明,复合微球没有改变g-C₃N₄与壳聚糖原有的结构。

The adsorption properties of chitosan and the photocatalytic properties of graphitic carbon nitride are utilized to prepare g-C₃N₄/chitosan composite microspheres to adsorb and reduce silver ions,and the obtained products are applied in surface-enhanced Raman substrates (SERS) to detect malachite green.Experimental results indicate that the prepared composite microspheres have a good adsorption capacity for silver ions,which reaches 152.17 mg·g^-1.The adsorption capacity of the composite microspheres adsorbed malachite green drops to 2%.The detection range for malachite green is 1×10^-7-1×10^-3 mol·L^-1,the characteristic peaks of SERS spectrum are obviously easy to distinguish,but the degradation ability of the composite microspheres will affect Raman detection to malachite green for a long time.It is shown by scanning electron microscope and energy spectrum analysis that the surface of the composite microspheres becomes rough,on which nano-silver is formed and distributes uniformly.XPS analysis results verify that silver on the surface of the composite microspheres is mainly elemental silver.Infrared spectroscopy analysis shows that the composite microspheres have not changed the original structure of g-C₃N₄ and chitosan.