Charge Transfer at the PTCDA/Black Phosphorus Interface

Abstract

The interfacial electronic structure at the organic–inorganic semiconductor interface plays an important role in determining the electrical and optical performance of organic-based devices. Here, we studied the molecular alignment and electronic structure of thermally deposited 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) molecules on cleaved black phosphorus using photoelectron spectroscopy. The work function of black phosphorus is substantially upped with an organic thin film, originating from the charge transfer from black phosphorus to PTCDA. According to our photoemission spectrum and theoretical simulation, we also define the interaction between PTCDA and black phosphorus as weak van de Waals physisorption, rather than bonding chemisorption. Furthermore, we show that PTCDA thin film can effectively isolate reactive oxygen species, thereby protecting BP surface oxidation and deterioration under ambient conditions. Our results suggest the possibility of manipulating interfacial electronic structures of black phosphorus interface by noncovalent with organic semiconductor, in particular for applications in high-performance organic–inorganic hybrid photovoltaic.

Demonstration of the key substrate-dependent charge transfer mechanisms between monolayer MoS2 and molecular dopants

“…The eD value can be determined from eD = ΔΦ -ΔVBM, with ΔVBM being the change in VBM binding energy before and after acceptor adsorption. From our data, eD is found to amount to 0.17 eV (sapphire), 0.36 eV (HOPG), and 0.55 eV (Au) 45,47,48 .…”

“…For examining the impact of n e on eventual CT, we also estimate the density ρ (e•cm −2 ) of charge transferred into the LUMO levels of F 6 TCNNQ molecules adsorbed on ML-MoS 2 by using the measured ΔΦ and VBM shift (ΔVBM), according to the Helmholtz equation 45,46 :…”

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

“…[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-…”

Functionalization of 2D Materials with Photosensitive Molecules: From Light‐Responsive Hybrid Systems to Multifunctional Devices

“…Therefore, they play a fundamental role in the functionalization of 2D crystals, especially those which do not possess π‐conjugated structure such as TMDs (e.g., MoS 2 , MoSe 2 , WS 2 , WSe 2 ) and black phosphorus. In particular, van der Waals interactions have been employed to assembly diazirines, spiropyrans, dihydroazulenes, azobenzenes, diarylethenes, perylene diimides, porphyrins, and phthalocyanines, especially metal‐derivatives in the last two cases, onto the surface of 2D materials in order to obtain photosensitive hybrid systems characterized by enhanced properties and performances. Finally, the noncovalent functionalization is a smart, poorly invasive and efficient approach to combine the remarkable properties of 2D materials with the fascinating and versatile photochemistry provided by light‐responsive molecular systems.…”