Silicone and pure organic binders were used to develop FAU-type zeolite coatings applied on pre-treated aluminum substrates by using a spraying method and then cured under specific conditions. The influence of the amount of binder on adhesion properties of zeolite coatings was first investigated to determine the optimum ratio between zeolite and binder. Zeolite coatings were then elaborated with a high zeolite content (between 70 and 80 wt.%) to ensure high adsorption capacities. The amount of binders involved in different zeolite coatings was sufficient to achieve interesting adhesion and cohesion properties. The accessibility of zeolite microporosity was studied by nitrogen adsorption-desorption measurements, which revealed a very small or no loss of the micropore volume for the optimized coatings. Volatile Organic Compounds (VOCs) adsorption measurements were carried out using n-hexane as probe molecule. FAU-type zeolite in powder form adsorbs 180 mg/g_{anhydrous zeolite}, whereas the amounts of n-hexane adsorbed by zeolite coatings ranged from 131 to 175 mg/g_{anhydrous zeolite}.

A vacuum chamber was designed to study the risk of laser-induced contamination (LIC) on optical payloads integrated on spaceflight missions. In this context, tests were performed with a nanosecond pulsed laser at 355 nm on fused silica substrates under toluene exposure with multiple laser irradiation. Specific experimental procedures are described in order to obtain repeatable results. Finally, series of tests were performed to investigate the onset of the LIC deposition process and its evolution over time. A slight antireflective effect is consistently observed at the onset of the deposition process. We suggest that this is an indication that the LIC deposition process in our experimental conditions starts with a nucleation layer consisting of small dense islands of deposit.

Lasers in space often suffer from light absorbing deposits forming inside the resonator. This effect is commonly called laser-induced contamination (LIC), and its mechanism can be compared with laser chemical vapor deposition. LIC experiments were carried out in a dedicated vacuum chamber using a q-switched 355-nm laser, hafnia- or silica-coated fused silica samples and contamination by epoxy adhesive outgassing, or toluene vapor in vacuum. The typical deposit formation was observed at different experimental conditions and analyzed by in situ laser-induced fluorescence imaging and ex situ white light interference microscopy. We determined the average growth rate during the first growth stage (bump-shaped growth) and analyzed it as a function of the laser fluence, sample nature, and used contamination. The data show that the band gap of the sample is important for the LIC process in the first growth stage. The light absorbed in the sample leads to a temperature rise that drives the deposit growth. This knowledge opens a new pathway to minimize LIC that is complementary to studies that aim to reduce the adsorption of contaminant molecules by making chemical surface treatments.

Cryogenic space-science missions have been expanding in the last few years. Onboard instruments, especially detectors, but also several parts of satellites can be cooled down to cryogenic temperature during cruise, commissioning phase and in operation. In such conditions, molecular contamination may happen and affect the performance of sensitive equipment. Polymer outgassing is the main source of contaminants, and this phenomenon is commonly studied from ambient temperature to high temperature, usually $125°\mathrm{C}$ . However, very few experimental data exist and there is no real evidence that tends to confirm that outgassing is negligible at temperature below $0°\mathrm{C}$ . This work aimed at studying the outgassing of some representative materials such as multilayer insulation and adhesives at low temperature. A multistep temperature profile from $-75$ to $25°\mathrm{C}$ has been applied to the materials and deposition kinetics measured using cryogenic quartz crystal microbalance. The results showed different interesting behaviors and highlighted outgassing beginning at $-75°\mathrm{C}$ . Based on these results, long-term predictions have been calculated with internal simulation tool. Moreover, in situ analysis of outgassed molecules has been attempted with a residual gas analyzer.

Laser-induced contamination (LIC) presents a critical challenge for the lifetime and performance of laser systems operating in vacuum, particularly in space and quantum optics applications. LIC occurs when high-intensity laser light interacts with organic molecules outgassed from surrounding materials and results in the formation of photo-fixed, fluorescent, light-absorbing organic deposits on laser-irradiated optical surfaces. Although the majority of previous research was focused on mitigating LIC for specific space missions, we take a more fundamental approach and provides insight into the physical mechanisms involved in both LIC’s deposition and laser cleaning processes. LIC deposits were created and cleaned in vacuum under a 355-nm nanosecond laser irradiation using the outgassed species of an epoxy-based adhesive as contaminants. Both the LIC deposition and cleaning processes were monitored in situ using laser transmission, pressure, visible light emission, and gas-phase mass spectrometry measurements. Our results confirm that the cleaning process is driven by a laser activated oxygen-based plasma. The mass spectrometry data show the chemical changes in the vapor composition inside the chamber during the cleaning process. Our findings are further validated with ex situ time-of-flight secondary ion mass spectrometry (ToF-SIMS) and optical profilometry measurements. Together, these results provide a more quantitative understanding of the chemical processes underlying the cleaning of LIC and offer an additional approach for investigating the LIC phenomena.