New metal oxide glass to block ultraviolet rays

Beijing, Jan 21 (PTI) Researchers in China have created a special metal oxide transparent glass with long lifetimes that can help protect living cells by absorbing and blocking damaging ultraviolet (UV) rays.

The dangers of UV light prompted scientists from the South China University of Technology to search for versatile materials that block UV and can withstand long radiation exposure times without falling apart.

They demonstrated that the new glass effectively protects living cells and organic dyes, and believe it could also be developed as a transparent shield to protect electronics in space.

The researchers used a metal oxide - cerium (IV) oxide (CeO2) - well-known for its ability to absorb UV photons to craft the composite glass-based UV absorber.

Other key features of the final composite material are the optical transparency of the glass and the materials ability to suppress the separation of photo-generated electrons and holes.

This slows down a light-induced reaction that would lead to the ultimate breakdown of the material under prolonged exposure to UV radiation.

The method the team developed is based on the self-limited nanocrystallisation of glass.

"Self-limited nanocrystallisation of glass can be achieved by taking advantage of the rigid environment of the solid-state matrix, rather than the conventional solution and vapour conditions to modulate the ionic migration kinetics," said Shifeng Zhou from South China University of Technology.

"It allows us to create glass-ceramics embedded with a CeO2:fluorine (F) nanostructure," Zhou added.

The groups innovative approach for fabricating the UV absorber has important implications "for the construction of novel glass materials with new functions via microstructure engineering," researchers said.

Among the groups key discoveries was finding that the self-limited nanocrystallinization of glass is indeed an effective way to functionalise it.

The special glass they created suppresses photocatalytic and catalytic activity, while boasting an extremely high UV-absorbing capacity.

Potential applications for the groups work include radiation hardening of electronic devices, serving as a biological shield, and preserving cultural artifacts and relics.

The findings were published in the journal Optical Materials Express. PTI SAN SAR SAR