Fine-tuning nanoparticle size by oligo(guanine)_n templated synthesis of CdS: An AFM study

We are presenting a method for modulating the size of CdS nanoparticles by templating their formation with oligo(guanine)_noligomers where n varied from 5 to 20. The variation in template length resulted in observable changes in the size distribution of the CdS nanoparticles. Statistical analysis of AFM images showed a general trend whereby the CdS average height decreased for longer oligoG_n and increased for shorter oligoG_n. Concomitantly, shorter oligoG_n yielded more dispersed populations, while longer oligoG_n gave less dispersed populations. This synthetic methodology could be extended to the synthesis of other nanoparticles and even to mixed-metal nanoparticles resulting in a powerful method for fine-tuning size-dependent properties.