Innovative nanomaterials processing points to advances in semiconductor optoelectronics

Electron diffraction pattern of PbS nanoparticles in zeolite X

Optical and structural properties of PbS nanoparticles produced in Zeolite Na-X

The study of semiconductor nanoparticles embedded in a matrix is currently a very active research area. These small particles have physicochemical properties quite different from those in the bulk material. A great variety of semiconductors nanoparticles have been synthesized in different matrix such as polymers, glasses and zeolites with the main purpose to modify their properties by controlling the particle size. Alterations to these properties mean they can be tailored to specific applications in the fields of non-linear optics, photovoltaic conversion, catalysis, optoelectronics, etc.

In this work, published in AZojomo*, by M. Flores-Acosta, R. Pérez-Salas, M. Sotelo-Lerma, F. F. Castillón-Barraza and R. Ramírez-Bon from Unidad Querétaro, Universidad de Sonora and Universidad Nacional Autónoma de México, PbS nanoparticles were synthesized in zeolite Na-X by means of ionic exchange processes in alkaline aqueous solutions. They reported the optical and structural properties of the system PbS-Na-X zeolite.

The 4.0nm PbS nanoparticles have spherical shape, the crystalline structure of galena and are embedded uniformly in the zeolite matrix. The 1se-1ph and 1pe-1ph excitonic transitions observed in the absorption spectra of the PbS-Na-X system is explained in terms of the crystalline quality of the PbS nanoparticles.

The results show that spherical PbS nanoparticles are formed not inside the zeolite cages but outside, embedded in the zeolite matrix. The absorption spectra of the samples display exciton absorption bands at much higher energy than the fundamental absorption edge of bulk PbS. This result is a consequence of strong quantum confinement effects produced by the reduced size of the PbS nanoparticles as compared to the exciton Bohr diameter of bulk PbS.

Media Contact

Dr. Ian Birkby EurekAlert!

More Information:

http://www.azonetwork.com

All latest news from the category: Physics and Astronomy

This area deals with the fundamental laws and building blocks of nature and how they interact, the properties and the behavior of matter, and research into space and time and their structures.

innovations-report provides in-depth reports and articles on subjects such as astrophysics, laser technologies, nuclear, quantum, particle and solid-state physics, nanotechnologies, planetary research and findings (Mars, Venus) and developments related to the Hubble Telescope.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors