Speaker: Pro. Wiesław Stanisław Stręk
Topic: Laser-Induced Hydrogen Generation from alcohols and water using Graphene as a Target
Date: April 18th, 2024 (Thursday)
Time: 9.00-10.00 a.m.
Venue: Room 428, School of Physics and Electronic Engineering
Sponsors: School of Physics and Electronic Engineering, Institute of Science and Technology
Biography:
He received a PhD degree in at the Institute of Low Temperature and Structure Research, Polish Academy of Sciences in Wroclaw in 1979 and Full Professor title in 1991. Employed at the Institute of Low Temperature and Structure Research, Polish Academy of Sciences in Wroclaw since 1971. His research activity covers laser spectroscopy, luminescence properties of rare earth and transition metal ions in crystal, glasses and nanostructures, theory of electronic relaxation (f-f and d-d radiationless transitions, multiphoton transitions in rare earth complexes, cooperative interactions) in metal complexes, nonlinear optics, sol-gel materials, nanotechnology, size-effects in nanomaterials, nanomaterials for fuel cells, nanophosphors, optical nanoceramics, optical sensors, biophysics (photodynamical therapy, bioimaging, cryotherapy). Author/co-author of around 800 papers with more than 13000 citations (without self-citations), Hirsch index-57. Co-author of more than 35 patents and patent applications in optical security, nanotechnology, cryotherapy, laser therapy, sol-gel technology, phosphors, thermal insulation porous materials, magnetic materials. Visiting professor at institutes and universities in France, Denmark, Brazil, Israel, Belarus, Russia, Vietnam, Italy, Germany.
Member of editorial boards of Journal of Alloys and Compounds (Elsevier), Journal of Rare Earth (Elsevier), Reports in Physics (Elsevier), Polish Materials Science, ISRN Spectroscopy, Acta Bio-Optica et Informatica Medica.
Abstract:
The present work demonstrates a new concept of the efficient generation of hydrogen from alcohols by the continuous wave laser diode irradiation of an immersed graphene aerogel (GA) scaffold as target. It was observed that the process occurred very intensively when it was assisted by bright white light emission in the spot of laser irradiated GA scaffold. The yield of hydrogen emission increased exponentially with the applied laser power. The light emission was assisted by the intense production of H2, CH4 and CO gases. It was found that with increasing excitation laser power, the H2 generation increased at the expense of CO. It is shown that the volume of CO decreases due to the formation of C2 molecules and CO2 gases. The mechanism of the laser driven dissociation of methanol was discussed in terms of the violent ejection of hot electrons from the GA surface as a result of the laser induced light emission of the graphene target.