Dear Colleagues,

Organic electronics is still a very new interdisciplinary field of physics, chemistry, and electronics that offers new applications due to the almost unlimited variability of organic materials, low-cost fabrication, suitable electrical properties, mechanical flexibility, and optical transparency. The very first devices have already reached the market and the market share growth is amazing for such novel technology that is still improving day by day. The charge mobility has increased by several orders of magnitude in the last decades and device performance is now challenging inorganic semiconductor devices. On the other hand, although some basic principles have already been revealed, fundamental research is still needed for the further development of devices, since the underlaying physics is still unclear and working principles need to be clarified. Actually, it is fascinating to state that “yes, it works, but we are still not sure why”.

It is my pleasure to invite you to submit a manuscript to this Special Issue that will be dedicated to the amazing field of organic semiconductors and organic electronic devices. Full papers, communications, and reviews are all welcome. We expect submissions covering the following topics:

• Challenges in the design, synthesis, and processing of organic materials
• Molecular order, defects, and interfaces including nanocomposites
• Characterization techniques for organic semiconductors and organic electronic devices
• Organic materials for energy harvesting
• Organic light-emitting diodes (OLEDs)
• Organic spintronics
• Organic sensors and biosensors
• Integration and technology for large areas and flexible electronics

The development of organic electronics is not only about the fundamental science, but it has significant industrial applications. Nowadays, organic electronics is present mostly in OLED displays, however our aim should be to find more common applications such as healthcare, photovoltaics, sensors, and low-power systems to improve the quality of life of human society by enabling high-end devices for everyone.

Assoc. Prof. Martin Weis
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• organic semiconductors
• organic field-effect transistors
• organic light-emitting diodes (OLEDs)
• organic solar cells
• organic spintronics

Innovative thermographic inspection of degradation in OPVs and OLEDs

Anna Stoynova

Unlike organic devices, their inorganic analogues are somewhat unstable and their performance degrades over time. The reliability of OLEDs and OPVs is crucial because of their degradation during storage and operation. The three physical mechanisms of degradation (interface conductive properties worsening; conjugation loss and irreversible deterioration of the active organic layers; mechanical disintegration of device) lead to changes in electrical properties and, in some cases, affect thermal behavior. The basic requirement of the absorbing or emissive technology with respect to products life is to ensure their quality and reliability. Stability for different OPVs applications requires different criteria. For solar cells, the requirements with the exposure to the external environment are different, and for the OLEDs it is important the fact that many organic molecules degrade when exposed to light. Known degradation mechanisms include diffusion of molecular oxygen and water into of interfaces, interlayer and electrode diffusion, electrode reaction with the organic materials, electrode oxidation, phase segregation or intermixing, delamination of any layer, and the formation of particles, bubbles, cracks etc. Various degradation mechanisms are associated with the bulk active layers and top contact. The use of flexible substrates for both technologies brings additional challenges. This chapter presents an innovative study of thermal behavior in degradation processes based on optimized thermographic non-destructive testing and diagnostics to improve products quality.