Artist’s impression of small clusters of silver atoms (green spheres) trapped in zeolite cages. Credit: Dr Oliver Fenwick.The toxic and expensive phosphors used widely in fluorescent lighting could be eliminated thanks to a new study conducted by a team that included a materials scientist at Queen Mary University of London (QMUL) in the UK.
Writing in Nature Materials, the international team of scientists reports modifying a mineral called zeolite, which is more commonly found in washing powder, to incorporate tiny clusters of silver atoms. At this atomic scale, the silver clusters, each comprising less than 10 atoms, act very differently from bulk silver and can even emit light.
"We've shown that silver atoms can be assembled in the porous framework of minerals known as zeolites with a level of control not reported previously," said lead author Oliver Fenwick from QMUL's School of Engineering and Materials Science. "This has allowed us to tailor very precisely the properties of the silver clusters to meet our needs – in this case an efficient phosphor.
"The high efficiency of the materials along with cheap, scalable synthesis makes them very attractive as next generation emitters for fluorescent lamps, LEDs and for biological imaging, for example for highlighting tumors or cell division."
Zeolites are porous minerals that can be found naturally or produced synthetically on an industrial scale. They are rigid and have a well-defined framework made of molecular-scale channels and cavities.
The researchers from Université de Strasbourg in France, where Fenwick was based when carrying out the study, and KU Leuven in Belgium manipulated the characteristics of the zeolite pores to fine-tune the properties of the silver clusters. By tailoring the zeolite host in this way, they were able to achieve luminescence efficiencies close to 100%.
This story is adapted from material from Queen Mary University of London, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.