In this work, organic photodiodes (OPDs) based on two newly synthesized p-type dipolar small molecules are reported for application to green-light-selective OPDs. In order to reduce the blue-color absorption induced by the use of C60 as the n-type material in a bulk heterojunction (BHJ), the electron donor:electron acceptor composition ratio is tuned in the BHJ. With this light manipulation approach, the blue-wavelength external quantum efficiency (EQE) is minimized to 18% after reducing the C60 concentration in the center part of the BHJ. The two p-type molecules get a cyanine-like character with intense and sharp absorption in the green color by adjusting the strength of their donating and accepting parts and by choosing a selenophene unit as a π-linker. When combined to C60, the green-wavelength EQE reaches 70% in a complete device composed of two transparent electrodes. Finally, the optical simulation shows the good color-balance performance of hybrid full-color image sensor without an additional filter by using the developed green OPD as the top-layer in stacked device architecture.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OE.27.025410 | DOI Listing |
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!