Competitive Adsorption between a Polymer and Its Monomeric Analog Enables Precise Modulation of Nanowire Synthesis

Capping ligand adsorption and desorption on crystal facets crucially affects the final crystal size and shape. Herein, based on the competitive adsorption of polyvinyl pyrrolidone (PVP) and its monomeric analog, cyclopentanone (CPK), we precisely modulate the synthesis of two different elemental nanowires; i.e., single-crystalline Te nanowires and multiple-twinned Pd nanowires. We discover that the similarity between the molecular structure of CPK and the repeating unit of PVP makes the competitive adsorption between them accessible, and the different desorption rates of PVP and CPK result in different crystal growth inhibition effects (strong for PVP and weak for CPK). Thus, the competitive adsorption between PVP and CPK leads to the precise modulation of the growth of these nanowires, which can be further illustrated by density functional theory. This work presents new opportunities to modulate the synthesis of nanocrystals by competitive adsorption between polymer ligands and their monomeric analogs.