Abstract
In this study, we successfully synthesized well-defined polygonal gold microplates for the first time in an aqueous phase using hydroxyethylcellulose (HEC) in the presence of hydrogen peroxide (H(2)O(2)). HEC played a pivotal role during the synthesis, acting not only as a biotemplate but also as an in situ reduction site for the nucleation and growth of gold (Au) microplates. H(2)O(2) played a crucial role in accelerating the growth of Au microplates from the Au nucleus. This methodology is ecofriendly and easy to operate and has potential applications in various fields, such as electronics, photonics, and biotechnology.