Nanoscale morphology and electronic coupling at the interface between indium tin oxide and organic molecular materials

Abstract

The correlation between nanoscale morphology and charge injection rates at the interface between an organic semiconductor layer and a transparent metal oxide electrode was investigated by integrating molecular dynamics simulations with electronic structure calculations. The simulation approach proposed has been applied to the analysis of the hole injection mechanism at the interface between an amorphous layer of tris[(3-phenyl-1H-benzimidazol-1-yl-2(3H)-ylidene)-1,2-phenylene]Ir (DPBIC), a hole transport and emitter molecule, and the surface of indium tin oxide (ITO), a material commonly used as anode in OLEDs. The link between interface morphology and charge injection was investigated by implementing a two-step, top-down simulation approach. Namely, nanoscale molecular aggregation phenomena at the organic/electrode interface were first assessed by molecular dynamics simulations, mimicking different processing conditions, and followed by density functional theory calculations of the electronic coupling between molecular levels and the manifold of electrode states involved in the charge injection process. The correlation between structural parameters and electronic coupling suggests a significant role of specific molecule/electrode configurations on charge transport processes at the interface, resulting in a broad distribution of charge injection rates, and highlights the link between molecular structure, nanoscale aggregation and processing in the realization of heterointerfaces for efficient charge injection in organic electronic devices.

The Impact of the Surface Modification on Tin-Doped Indium Oxide Nanocomposite Properties

“…Few works have been performed using MD simulation to study both the interface properties and doping mechanism in ITO [ 62 , 63 ]. For this purpose, MD is first performed to relax the surface structure of the ITO.…”

“…Lorenzoni et al also used MD to simulate the nanoscale morphologies of ITO and organic conductive molecules (Iridium complex Tris DPBIC (3-phenyl-1H-benzimidazol-1-yl-2(3H)-ylidene)-1,2-phenylene)). Their goal was to study the charge injection mechanism at the interface of the metal/organic complex [ 63 ]. They performed a two-step, top-down simulation approach.…”

3D versus 2D Electrolyte–Semiconductor Interfaces in Rylenediimide‐Based Electron‐Transporting Water‐Gated Organic Field‐Effect Transistors

“…[56] This computational approach reproduces the structure of molecular aggregates that are in excellent agreement with experiments. [57][58][59][60] The water molecules were simulated using the TIP4P model. The Berendsen thermostat was used for simulations in the NVT and NPT with time constants of 0.1 and 1.0 ps, respectively.…”

Noncovalent passivation of supported phosphorene for device applications: from morphology to electronic properties

“…The morphology of alkane aggregates growing on phosphorene under kinetic and thermodynamic control has been simulated by a combination of non-equilibrium and equilibrium MD, as described in previous work. 32,33 Initially, amorphous aggregates of alkanes on phosphorene were generated by progressively adding individual alkane chains, relaxed at 300 K, to the phosphorene surface at an interval of 50 ps. Positions of alkane chains on the xy periodic plane were assigned randomly at a distance of 5 nm from the phosphorene surface on the non-periodic z direction.…”