Researchers at Oregon State University are working with a highly durable organic pigment called xylidein derived from wood-eating fungi, as an alternative to silicon in optoelectronic applications, such as solar cells.

Optoelectronics is technology working with the combined use of light and electronics. The pigment, xylindein, is derived from wood-eating fungi in the Chlorociboria genus, which stain any wood affected with a blue-green colour. The pigment has been used in artwork for hundreds of years.

The researchers found that the pigment functions as an electronic material, but not a great one. Their aim is to make it better. Xylindein is so stable that decorative products from hundred of years ago still have their distinct hue. It also holds up against prolonged exposure to heat, ultraviolet light, and electrical stress.

Many organic electronic materials are expensive to produce, unlike the fungi material. However, with the current fabrication techniques, the pigment tends to form non-uniform films with a porous, irregular and “rocky” structure.

The researchers blended xylindein with a transparent, non-conductive polymer called poly(methacrylate), also known as PMMA. The PMMA greatly improved the film structure without a detrimental effect on xylindein’s electrical properties. In addition, the blended film showed better photosensitivity.

In further research, the researchers will look at replacing the polymer with a natural product, preferably something made from cellulose.

Xylindein won’t beat silicon, but it does offer possibilities for, for example, wearable electronics.

Photo: Oregon State University