Mithrene Is a Self-Assembling Robustly Blue Luminescent Metal–Organic Chalcogenolate Assembly for 2D Optoelectronic Applications

Abstract

Crystalline metal−organic chalcogenolate assemblies are a class of semiconducting hybrid nanomaterials that consist of well-defined arrays of nanostructured inorganic coordination polymers with a supramolecular lattice of organic ligands. Growing crystals of periodic arrays of nanostructured hybrid chalcogenolates at biphasic liquid−liquid interfaces has been used to prepare semiconducting hybrid materials for potential applications in sensing, catalysis, mechanochemistry, organic light-emitting devices, and photovoltaics. However, a distinct lack of a systematic framework for quantifying the relationship between experimental parameters and the structure−function relationship of the prepared materials has been one of the largest hurdles for the emerging field of hybrid chalcogenolates and related hybrid coordination polymer systems.Here we examine the crystallization of silver benzeneselenolate, coined here as mithrene, at a toluene−water interface and demonstrate that silver ion concentration is the critical variable for controlling the morphology of the semiconducting crystals. Confocal microscopy is used to demonstrate that the blue luminescence of the material is robust across all morphologies. The role of metal ion concentration on the structure and morphology of the hybrid chalcogenolate is considered, and the properties of the crystalline and amorphous products are compared. Grazing-incidence wide-angle X-ray scattering is used to demonstrate that the crystallographic phase of the crystals in sparse layers is uniform across all morphologies. The observation of blue luminescence can be used as a reliable proxy for the crystalline phase in future work. The straightforward synthetic preparation for and robust optoelectronic properties of silver benzeneselenolate make it an ideal model system for the development of device and sensor applications leveraging the emerging class of metal−organic chalcogenolates.

Metal Nanoclusters Stabilized by Selenol Ligands

“…Accordingly, SeR‐SAMs always display enhanced stability compared to SR‐SAMs . Similar laws have also been observed in Ag SAMs . In this context, it is anticipated that SeR‐stabilized nanoclusters will display enhanced stability compared to their thiolated analogues.…”

“…The use of selenols as ligands for nanoclusters was, historically, enlightened from the stability comparison of SR/SeR (thiol/selenol) capped self‐assembled monolayers (SAMs)—the interactions between Au from Au{111} and Se from selenols in SeR‐SAMs were much stronger than that of the SR‐SAMs (TeR‐SAMs were the most stable, as shown in Figure ) . Compared with the sulfur, the electronegativity and atomic radius of selenium are closer to those of the gold, resulting in more a covalent bond of Au–Se relative to Au–S .…”

Transparent and luminescent glasses of gold thiolate coordination polymers

“… 11 The peculiar optical properties displayed by anisotropic 1D and 2D MOCs have demonstrated their great potential for temperature sensing and optoelectronic applications. 12 They are thus a good alternative to replace the lanthanide-based luminescent materials considered as critical elements and even banned by the European Union. 13…”

Anisotropic 2D excitons unveiled in organic–inorganic quantum wells

“…While few previous studies have investigated such self-assembled hybrid metalorgano-chalcogen coordination networks, 12,13,46,48 the optoelectronic properties of these quantum-confined systems and their potential tunability due to structural design are still largely unexplored. [14][15][16]47 Importantly, due to their structural complexity, ab initio calculations of the excited state properties in these materials, as well as a comprehensive understanding of the relation between the electronic and excitonic properties and the atomic configuration, are lacking. In this study, we use an optical pump detuning of transient absorption spectroscopy 17 to determine an exciton binding energy higher than 380 meV in layered bulk silver benzeneselenolate, which we denote as [AgSePh] N where Ph indicates interlayer phenyl groups.…”