Doping Phosphorene with Holes and Electrons through Molecular Charge Transfer

Abstract

An important aspect of phosphorene, the novel two-dimensional semiconductor, is whether holes and electrons can both be doped in this material. Some reports found that only electrons can be preferentially doped into phosphorene. There are some theoretical calculations showing charge-transfer interaction with both tetrathiafulvalene (TTF) and tetracyanoethylene (TCNE). We have carried out an investigation of chemical doping of phosphorene by a variety of electron donor and acceptor molecules, employing both experiment and theory, Raman scattering being a crucial aspect of the study. We find that both electron acceptors and donors interact with phosphorene by charge-transfer, with the acceptors having more marked effects. All the three Raman bands of phosphorene soften and exhibit band broadening on interaction with both donor and acceptor molecules. First-principles calculations establish the occurrence of charge-transfer between phosphorene with donors as well as acceptors. The absence of electron-hole asymmetry is noteworthy.

Chemistry of Layered Pnictogens: Phosphorus, Arsenic, Antimony, and Bismuth

“…The strategy of functionalization was also based on the same approach using electron‐accepting large polyaromatic molecules. Interactions of electron donors (for example, tetrathiafulvalene) and acceptor (for example, tetracyanoethylene) with phosphorene were studied by Rao et al . The obtained results were confronted with the theoretical calculations of electron density and DOS.…”

“…These acceptors are strongly interacting with black phosphorus surface and are able to significantly change its electronic properties. [30] Thee lectron-withdrawing effect led to the enhancement of the hole concentration within the layers.T he strategy of functionalization was also based on the same approach using electron-accepting large polyaromatic molecules.I nteractions of electron donors (for example,t etrathiafulvalene) and acceptor (for example, tetracyanoethylene) with phosphorene were studied by Rao et al [31] Theo btained results were confronted with the theoretical calculations of electron density and DOS.T he shift of three main Raman bands was observed for the black phosphorus non-covalently modified with electron-withdrawing and injecting molecules.3 ,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) is another example of an electronaccepting molecule used for non-covalent modification of black phosphorus. [32] Compared to the other methods of preparation, this non-covalent functionalization was per-…”

2D Elemental Nanomaterials Beyond Graphene

“…All the three Raman modes show softening as well as broadening on both electron and hole doping, with the hole doping causing more marked effects (Figure c–h). Tetrathiafulvalene (TTF), tetracyanoethylene (TCNE) as well as many other organic molecules have been employed for molecular charge‐transfer studies . Raman scattering of phosphorene is affected by temperature .…”

Von‐Hippel‐Preis: C. N. R. Rao / Ernst‐Haage‐Preis: H. Oberhofer / Meyer‐Galow‐Preis: M. Heitzmann

“…Sein Interesse gilt der Festkörper‐ und Materialchemie sowie der Strukturchemie und schließt die Eigenschaften von Übergangsmetalloxiden und Nanomaterialien, die künstliche Photosynthese und die Wasserstofferzeugung ein. In ChemNanoMat hat er kovalent funktionalisierte Nanopartikel aus halbleitenden Metallchalkogeniden vorgestellt und in ChemPhysChem das elektronische Dotieren von Phosphoren . Rao gehört den Editorial oder Advisory Boards von Chemistry—An Asian Journal (das anlässlich seines 75.…”