Stable and adhesive hybrid fluorescent sol-gel coating on pre-treated stainless steel: application to the realization of optical fluorescence sensors

New organic-inorganic sol-gel films have been prepared starting from mixtures of silicon and zirconium alkoxides using a multi-step synthesis process. The coatings have been deposited on stainless steel rendered adhesive towards the gels by an oxidative surface treatment and have been loaded with a fluorescent powder. The final deposits with or without loading, have successfully survived drastic standard adherence tests before and after several dips into liquid nitrogen. Fluorescence spectra and decay have been investigated showing that the fluorescent sol-gel coating is very attractive to realize non-contact optical cryogenic temperature sensor.