Heterometallic Benzenehexathiolato Coordination Nanosheets: Periodic Structure Improves Crystallinity and Electrical Conductivity.
Ryojun ToyodaNaoya FukuiDionisius H L TjheEkaterina SeleznevaHiroaki MaedaCédric BourgèsChoon Meng TanKenji TakadaYuanhui SunIan JacobsKazuhide KamiyaHiroyasu MasunagaTakao MoriSono SasakiHenning SirringhausHiroshi NishiharaPublished in: Advanced materials (Deerfield Beach, Fla.) (2022)
Coordination nanosheets are an emerging class of 2D, bottom-up materials having fully π-conjugated, planar, graphite-like structures with high electrical conductivities. Since their discovery, great effort has been devoted to expand the variety of coordination nanosheets; however, in most cases, their low crystallinity in thick films hampers practical device applications. In this study, mixtures of nickel and copper ions are employed to fabricate benzenehexathiolato (BHT)-based coordination nanosheet films, and serendipitously, it is found that this heterometallicity preferentially forms a structural phase with improved film crystallinity. Spectroscopic and scattering measurements provide evidence for a bilayer structure with in-plane periodic arrangement of copper and nickel ions with the NiCu 2 BHT formula. Compared with homometallic films, heterometallic films exhibit more crystalline microstructures with larger and more oriented grains, achieving higher electrical conductivities reaching metallic behaviors. Low dependency of Seebeck coefficient on the mixing ratio of nickel and copper ions supports that the large variation in the conductivity data is not caused by change in the intrinsic properties of the films. The findings open new pathways to improve crystallinity and to tune functional properties of 2D coordination nanosheets.
Keyphrases
- reduced graphene oxide
- room temperature
- quantum dots
- metal organic framework
- oxide nanoparticles
- carbon nanotubes
- gold nanoparticles
- ionic liquid
- highly efficient
- high resolution
- photodynamic therapy
- molecular docking
- magnetic resonance
- magnetic resonance imaging
- aqueous solution
- high throughput
- machine learning
- transition metal
- computed tomography
- contrast enhanced
- mass spectrometry