OBJECTIVES Investigation of the physical properties of silver nanowire networks for transparent electrodes and transparent heaters:
understanding the relationship between silver nanowire morphology & network density and the physical properties (electrical, optical, thermal…),
investigating the effects of post-treatment such as thermal annealing on electrical properties,
models of physical properties,
integration of silver nanowire networks into devices.
NON PERMANENT STAFF
Sara Aghazade (PhD student)
Afzal Khan (Visitor)
Thomas Sannicolo (PhD student, LMGP-CEA joint PhD)
Dr. J.-P. Simonato, CEA-Liten, Grenoble (France)
Prof. N.D. Nguyen (Liège, Belgium)
Prof. Y. Bréchet, Grenoble INP (France)
Prof. J.N. Coleman, Trinity College Dublin (Ireland)
Silver nanowire (AgNW) networks can exhibit very good electrical, thermal and optical properties, especially after thermal annealing. We have recently shown (Langley, Nanoscale 2014) the effects of a thermal annealing which allows: i) the formation of efficient percolating pathways; and ii) the local sintering at junctions between nanowires leading to a low electrical resistance. Above a certain annealing temperature Rayleigh instability does occur thus destroying the percolative nature of AgNW networks.
Such networks can also efficiently act as transparent heaters. A comprehensive model has been developed for describing the physics of such nanostructured transparent heaters (Sorel et al., ACS 2014).
a) Evolution of the electrical resistance of a AgNW network during a continuous thermal ramp; b-e) SEM images of: (b) as-deposited sample and of specimen annealed for 10 minutes at different temperatures: (c) 200°C, first occurrence of observable sintering; (d) 300 °C all junctions are sintered; (e) 380 °C complete spheroidization of the network. The scale bars in images b), c) and d) are 1 µm whereas that of image e) is 4 µm. (Ref: D.P. Langley et al. Nanoscale, to be published)
S. Sorel, D. Bellet, J.N. Coleman, The relationship between material properties and transparent heater performance for both bulk-like and percolative networks, ACS Nano 8 (2014) 4805
D.P. Langley, G. Giusti, M. Lagrange, R. Collins, C. Jimenez, Y. Bréchet, D. Bellet, Silver nanowire networks: physical properties and potential integration in solar cells, Solar Energy Materials & Solar Cells, 125 (2014) 318-324.
D.P. Langley, G. Giusti, C. Mayousse, C. Celle, D. Bellet, J.-P. SIimonato Flexible transparent conductive materials based on silver nanowire networks: a review, Nanotechnology 24 (2013) 452001055709.