Developing unbreakable screens
Cracked phone screens could become a thing of the past thanks to breakthrough research by a global team of scientists.
They have unlocked the technology to produce next-generation composite glass for lighting LEDs as well as smartphone, television and computer screens.
The findings will enable the manufacture of glass screens that are not only unbreakable but also deliver crystal clear image quality.
The collaboration involved scientists and engineers from the University of Leeds, University of Cambridge, UniversiteĢ Paris-Saclay, and was led by the University of Queensland in Australia. The findings have been published in the journal Science.
The research is focused on nanocrystal materials known as lead halide perovskites, which are promising candidates for light emitting diodes. The breakthrough has been the ability to stabilise a particular crystal at room temperature.
A nanocrystal is less than 100 nanometres in size, where a nanometre is one-billionth of a metre.
Dr Sean Collins, University Academic Fellow in the School of Chemical and Process Engineering at Leeds and a member of the research team, said: “Normally, the iodine-containing lead-halide perovskite (CsPbI3) crystal turns into an inactive material at room temperature, and this inactive material does not emit light efficiently.
“The glass matrix we have developed freezes the bright, active crystal structure and prevents it from deactivating.
“What is even more exciting is that the glass matrix protects the active material from ambient humidity or damage from heat or light exposure. These are persistent problems with halide perovskite materials.
“The result is a material that can deliver colour purity for displays and energy-efficient lighting.”
Picture quality and strength
The research used a new type of glass developed at the University of Cambridge which is hard to crack or shatter. At the moment, studies have been restricted to the laboratory, but the researchers hope it would enable a new generation of LEDs to be mounted into very tough glass. The University of Queensland is patenting the technology.
Dr Jingwei Hou, from the University of Queensland, said: “At present QLED or quantum dot light-emitting diode screens are considered the top performer for image display and performance. This research will enable us to improve on this nanocrystal technology by offering stunning picture quality and strength.”
At the University of Leeds, scientists used advanced imaging techniques to investigate the light-emitting nanocrystals. Dr Collins said: “To be able to see individual nano-sized crystals in the glass matrix and to determine the structure of each crystal, we used an advanced microscope that uses electrons to see things that are too small to examine otherwise.”
The research at Leeds involved the Bragg Centre for Materials Research, the Leeds Electron Microscopy and Spectroscopy Centre and the Leeds EPSRC Nanoscience and Nanotechnology Facility as well as the Diamond Light Source, home to the UK’s synchroton, which acts as a powerful microscope.
