After efficiency, lifetime is the second most important parameter for organic devices. Interfaces play a major role in that lifetime. This article reviews the current state of the art with regards to interfacial stability and control of electrode/active layer interfaces to understand the performance of organic optoelectronic devices. From examples relating to interfacial chemical reactions, interfacial morphological changes, and interfacial electronic level modification, a comprehensive picture of the role of the organic–electrode interfaces in device stability can be formed. The review begins with a brief overview of degradation in organic devices, including definitions and measurement approaches. It is then broken into two sections. The first focuses on the bottom contact (substrate) interface, specifically chemical reactions and dewetting, as the two main mechanisms of device degradation. The second section examines the top contact interface, which is prone to oxidation, interdiffusion, blistering and delamination, and inhomogeneous loss of performance (dark spots). For both sections, various approaches to overcoming device instabilities are given, with special attention to the various interlayers that have been introduced into devices for improved stability. Each section also includes examples where the main degradation mechanism is used advantageously to produce novel device architectures and surprising solutions to device degradation.

Metal–organic interfaces based on copper-phthalocyanine monolayers are studied in dependence of the metal substrate (Au versus Cu), of its symmetry [hexagonal (111) surfaces versus fourfold (100) surfaces], as well as of the donor or acceptor semiconducting character associated with the nonfluorinated or perfluorinated molecules, respectively. Comparison of the properties of these systematically varied metal–organic interfaces provides new insight into the effect of each of the previously mentioned parameters on the molecule–substrate interactions.

As sustainable energy becomes a major concern for modern society, renewable and clean energy systems need highly active, stable, and low-cost catalysts for the oxygen evolution reaction (OER). Mesoporous materials offer an attractive route for generating efficient electrocatalysts with high mass transport capabilities. Herein, we report an efficient hard templating pathway to design and synthesize three-dimensional (3-D) mesoporous ternary nickel iron nitride (Ni3FeN). The as-synthesized electrocatalyst shows good OER performance in an alkaline solution with low overpotential (259 mV) and a small Tafel slope (54 mV dec⁻¹), giving superior performance to IrO₂ and RuO₂ catalysts. The highly active contact area, the hierarchical porosity, and the synergistic effect of bimetal atoms contributed to the improved electrocatalytic performance toward OER. In a practical rechargeable Zn–air battery, mesoporous Ni₃FeN is also shown to deliver a lower charging voltage and longer lifetime than RuO₂. This work opens up a new promising approach to synthesize active OER electrocatalysts for energy-related devices.

Al/LiF cathode/organic is known to form an excellent interface for electron injection into the organic active layer, resulting in excellent performing organic light-emitting diodes (OLEDs). Here, the chemical structure of the interface between the Al/LiF bilayer cathode and tris (8-hydroxyquinoline) aluminum (Alq) of working OLED devices was investigated by using x-ray photoelectron spectroscopy (XPS). Using a in situ peel-off technique, we are able to characterize the buried interface structure without disturbing the chemical states of each element probed. The data show that there are two types of F at the interface; one is attributed to LiF and the other to F attached to the Alq. This F-doped Alq layer could induce a downshift in molecular orbital levels and thus leads to a reduced electron injection barrier. XPS depth profile results show significant O diffusion through Al layer to the interface, and the diffusion of O ends abruptly at the Al/LiF interface.