Effect of nanoparticle nature on hydrogen concentration profiles and improved switching characteristics in Gd switchable mirrors.
A detailed elastic recoil detection analysis using 40 MeV 28Si5+ ions has been carried out to study the changes in the H concentration and concentration profiles during the hydrogenation/dehydrogenation process in polycrystalline and nanoparticle Gd layers formed using vacuum evaporation and inert gas evaporation techniques, respectively. Nanoparticle sample exhibits a larger difference in the [H]/[Gd] values (2.9 and 1.7) in comparison to polycrystalline sample (2.4 and 2.0) in the loaded and deloaded states. Hydrogenation/dehydrogenation activity is restricted to the top portion in case of polycrystalline sample. In contrast to this, size induced structural transformation; enhanced surface area and the presence of large number of inter particle boundaries due to nanoparticle character result in the complete Gd layer becoming active during switching.
Aruna
I
I
Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India.
Mehta
B R
BR
Malhotra
L K
LK
Khan
S A
SA
Avasthi
D K
DK
D003460:Crystallization / Q000379:methods*; D004553:Electric Conductivity; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D005682:Gadolinium / Q000032:analysis / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D049329:Nanostructures / Q000032:analysis / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods; D055095:Optics and Photonics / Q000295:instrumentation*; D010316:Particle Size; D010777:Photochemistry / Q000295:instrumentation* / Q000379:methods; D013499:Surface Properties
D006859:Hydrogen; D005682:Gadolinium