Colloidal lead iodide nanorings. Issue 45 (12th November 2018)

• Record Type: Journal Article
• Authors: Klein, Eugen; Heymann, Leonard; Hungria, Ana B.; Lesyuk, Rostyslav; Klinke, Christian
• Is Part Of: Nanoscale. Volume 10:Issue 45(2018)
• Page Start: 21197
• Page End: 21208
• Publication Date: 2018-11-12
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c8nr06430j
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : We present the synthesis and characterization of PbI2 nanorings prepared via a direct colloidal route. The ring structures are obtained by etching as prepared PbI2 nanosheets with trioctylphosphine and possess thicknesses between 20 nm and 85 nm and lateral dimensions of up to 10 μm. The formation process was analyzed and discussed as well as the electrical and optical measurements. Abstract : Colloidal chemistry of nanomaterials experienced a tremendous development in the last decades. In the course of the journey 0D nanoparticles, 1D nanowires, and 2D nanosheets have been synthesized. They have in common to possess a simple topology. We present a colloidal synthesis strategy for lead iodide nanorings, with a non-trivial topology. First, two-dimensional structures were synthesized in nonanoic acid as the sole solvent. Subsequently, they underwent an etching process in the presence of trioctylphosphine, which determines the size of the hole in the ring structure. We propose a mechanism for the formation of lead iodide nanosheets which also explains the etching of the two-dimensional structures starting from the inside, leading to nanorings. In addition, we demonstrate a possible application of the as-prepared nanorings in photodetectors. These devices are characterized by a fast response, high gain values, and a linear relation between photocurrent and incident light power intensity over a large range. The synthesis approach allows for inexpensive large-scale production of nanorings with tunable properties.