表面吸附质对银亚胶体吸光特性的影响

纯银溶胶在390nm处有一吸收峰。当银溶胶吸附了1-苯基-5-巯基四氮唑(PMT)或2-巯基苯骈噻唑(MBT)时, 银溶胶由亮黄色转变为橙红色, 即在510～550nm处出现一个新的吸收峰。研究发现, 卤素离子在银溶胶颗粒上与PMT和MBT有竞争吸附作用。但是卤离子对银溶胶的光谱吸收的影响完全不同于PMT和MBT。在讨论这种差别时应首先考虑金属银溶胶颗粒表面性质因吸附不同物质所产生的变化。

The influences of adsorbates on the characters of spectral absorption of the silver subcolloid

While the pure silver sol has an absorption max. at 390 nm, the addition of phenylmercaptotetrazole (PMT) or mercaptobenzothiazole (MBT) to silver sol caused the color of the sol to turn orange, a new absorption peak appeared at 510-550 nm. The adsorption of halide ions competes with PMT and MBT. However, halide ions have shown a completely different influence on the spectral absorption of silver sol as compared to PMT and MBT. The different effects between PMT/MBT and halide ions due to adsorbed on silver surface on the spectral absorption resulted from the different interaction between silver and adsorbates.