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在水相体系中以柠檬酸钠和硝酸银为反应物,利用可见光诱导的还原过程在室温下制备盘状的银纳米粒子,通过紫外-可见光谱监控了不同反应条件下银纳米粒子的生长过程及体系的稳定性．吸收光谱随时间的变化表明,在一定的反应条件下早期的产物为球形粒子;随着反应时间延长盘状产物开始逐渐生成并长大,球形粒子数也进一步增加;而到了后期盘状粒子则通过粒子间的Ostwald熟化过程进一步长大．研究还发现,过量的柠檬酸根离子无助于稳定胶态体系,而适量的PVP(聚乙烯吡咯烷酮)的加入则能起到有效的稳定作用;严格控制的搅拌对于保证体系良好的分散稳定性不可缺少．进一步的研究还表明,在反应体系中引入大量的氢氧根离子能大大的加快反应速度．
In the aqueous system sodium citrate and silver nitrate as reactants, the use of visible light-induced reduction process at room temperature prepared silver nanoparticles, UV-Vis spectra of silver nanoparticles under different reaction conditions were monitored And the stability of the system. The changes of absorption spectra with time show that the early products are spherical particles under a certain reaction conditions. With the extension of reaction time, the discoidal products begin to grow up and grow up, and the number of spherical particles further increases. Grow further by Ostwald ripening between particles. The study also found that excessive citrate ion does not help stabilize the colloidal system, while the amount of PVP (polyvinylpyrrolidone) added can play an effective stabilizing effect; strict control of the mixing system to ensure good dispersion stability not lack. Further studies also show that the introduction of a large number of hydroxyl ions in the reaction system can greatly speed up the reaction rate.