Polymers containing Azobenzene chromophores have received much interest as photo-reversible materials for a variety of energy harvesting and transducing applications. Most recently, Azo Polymers that mimic the retinal photo-switch that enables vision have also been shown to respond physically and mechanically to light, to act as all-optical patterning materials, and simple photo-mechanical devices, where solar energy can be converted directly to mechanical work. In particular, a photo-induced pressure in soft amorphous thin films of azo polymers can lead to the facile inscription of various nanostructures, and efficient surface relief gratings (SRGs) upon irradiation with an interference pattern. Reversible changes in surface energy are also inducible as a result, for a variety of biomedical applications, such as guiding cell growth and function reversible and remotely via light.
Irradiation with CW light will be shown to lead to a measurable reversible photo-expansion of these films, of up to a few %, allowing the materials to function as photo-mechanical switches or light-actuators. New azo polymers to optimize this effect with be presented, and some simple macroscopic devices will be demonstrated that take mechanical advantage of this effect for larger scale motion driven by sunlight, such as bending, rolling, and 'walking'. The mechanism for this effect will be discussed from studies using ellipsometry, light-bending of AFM cantilevers, surface plasmon resonance spectroscopy, and neutron reflectometry.
Séminaire SPCSI - Informations pratiques
Afin de pouvoir entrer sur le site du CEA de Saclay veuillez adresser les données personnelles suivantes par courriel à Christine Prigian et Catherine Julien (secrétariat) un avis d’entrée vous sera alors délivré:
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Prénom:
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Ces informations doivent être envoyées au mieux deux jours avant la date du séminaire.
Lors de votre venue vous devez vous présenter avec une carte d'identité ou un passeport en cours de validité. L'entrée sur le site se fait par l'entrée principale ou porte Nord (suivre le lien ci-dessous), un badge vous y sera remis. Demandez à l'accueil le Bât.466, ils vous renseigneront.
Les séminaires se déroulent au Bât. 466, pièce 111 (1er étage).
En cas de problème vous pouvez contacter le secrétariat au : 01 69 08 65 32 / 40 12.
Formalities for entering the CEA Saclay site for SPCSI seminars
To enter in CEA Saclay you need to send the following personal data to Christine PRIGIAN and Catherine Julien (secretariat):
Informations: Access
Contact: Christine Prigian et Catherine Julien
Last Name :
First Name :
Place and date of birth :
Nationality :
Employer Name :
These informations must be preferably sent at least two days before the seminar date.
When you come you must have a valid ID card or passport with you.
The entrance in CEA Saclay is through the main entrance or north entrance (see link below), a pass will be delivered. Ask at the “accueil” the path for the building 466. SPCSI seminars take place in room 111 (first floor).
Any questions/troubles do not hesitate to contact our secretariat : 33 (0)1 69 08 65 32 / 40 12.