Accidentally made super-black wood sucks 99% light, could transform solar power

Sometimes, breakthrough developments happen accidentally in scientific exploration. Such is the story of “Nxylon,” a new super-black material that absorbs nearly all light.

The University of British Columbia researchers describe the discovery as a “sheer accident.” The unique structure of the black wood means it absorbs light without the need for pigments.

This exceptionally dark material has the potential to advance fields like astronomy, fashion, renewable energy, and optics.

“Nxylon’s composition combines the benefits of natural materials with unique structural features, making it lightweight, stiff and easy to cut into intricate shapes,” said Professor Philip Evans, who led the development.

The unexpected discovery

An unexpected outcome of Evans and PhD student Kenny Cheng’s laboratory experiments led to the creation of Nxylon.

Initially, the researchers experimented with plasma to increase the water resistance of wood. It was a routine experiment until something extraordinary happened.

Surprisingly, when the procedure was applied to the exposed ends of wood cells, they turned into an incredibly dark shade of black.

The team was baffled and intrigued at the same time. They worked with Texas A&M University’s physics and astronomy department to perform measurements of the dark substance.

Measurements revealed an astonishing fact: this material absorbed nearly all light, a property rarely found in nature. And that was their eureka moment.

“Ultra-black or super-black material can absorb more than 99 per cent of the light that strikes it – significantly more so than normal black paint, which absorbs about 97.5 per cent of light,” said Evans, a professor in the faculty of forestry.

Nxylon is primarily made from North American basswood. The material can also be created using European limewood.

“Nxylon can be made from sustainable and renewable materials widely found in North America and Europe, leading to new applications for wood,” noted Evans in the press release.

Use of this super-black material

Interestingly, Nxylon exhibited its exceptional properties by preserving its black color even after being covered with a gold coating for electron microscopy.

Unlike standard black paints, Nxylon doesn’t rely on pigments. Its unique structure traps light, making it exceptionally dark.

Ultra-black materials are in high demand for various applications.

In astronomy, they enhance image clarity by minimizing stray light. Solar cells benefit from their ability to absorb more sunlight. In addition, they’re prized for artistic creations like jewelry and luxury goods like watches.

Nxylon can breathe new life into the forestry industry, offering a sustainable and luxurious alternative to traditional materials. Its inky blackness has the potential to replace valued dark woods like ebony and rosewood in watchmaking.

Furthermore, it can serve as a viable replacement for costly black gemstone onyx in jewelry.

The team has created prototype products using their super-black wood. The initial focus is on high-end markets like watches and jewelry, but they envision a broader range of applications.

Dr. Evans and his team aim to commercialize Nxylon through a startup, collaborating with designers to create various products. They also plan to develop a reactor for large-scale Nxylon production.

The findings have been reported in the journal Advanced Sustainable Systems.