Self-Templated Assembly of AuI /AgI -Thiolate Sheets with Central Holes

Abstract

Composite crystalline sheets of Au^I /Ag^I -thiolate with central holes are achieved by co-assembly of Ag^I -thiolate and Au^I -thiolate in one-pot without sacrificial template. Both Ag^I -thiolate and Au^I -thiolate can separately assemble to lamellar sheets with similar structures, which makes their co-assembly possible, while the differences in their assembly pathways make the co-assembly processes highly dynamic and complex. First, a core@shell structure with Ag^I -thiolate at the core was formed upon the mixing of the two, then the core@shell structure transformed to a hole@shell structure by dissociation of the core. Finally, some instable hole@shell structures further dissociated and grew on stable ones to generate holed Au^I /Ag^I -thiolate composite sheets, in which the two components neither have severe phase separation nor blend uniformly at atomic level. By tuning the feeding ratios, the average diameter of the holes can be controlled. Therefore, the work demonstrates the advantage of co-assembly technique in obtaining complex structurers. The holed sheets can further assemble to porous macroscopic materials and transform to composite metal nanoparticles by pyrolysis.

Keywords: central holes; co-assembly; composite crystalline sheets; core@shell; gold thiolate; silver thiolate.