A novel approach is developed for washcoating metal−organic framework MIL-101 (Cr), a high-performance water adsorbent, uniformly on a cordierite honeycomb microchannel monolith. The methodology relies upon the characterization of the slurry, which consists of MIL-101 (Cr), SiO 2 nanoparticle binder, and a distilled water base and the adsorbent loading as its function. The adsorbent layer thickness is experimentally characterized as a function of viscosity and binder and MIL-101 (Cr) mass fraction. The highest normalized loading of 10%, at the optimized solid fraction of 6%, is identified, for which the layer thickness is remarkably high at 106 μm. The coated layers are analyzed for homogeneity, porosity, durability, and adsorbent property variations before and after coating through scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and ultrasonic vibration tests. While the adsorbent properties were retained after the washcoating process, the adsorbent layer showed excellent adhesion and durability after ultrasonic vibrations for 4800 h. The channels fabricated using this method can be readily scaled up in separation and heat pump systems.

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The recent advancement in multifunctional thermal barrier coatings (TBCs) for temperature sensing or defect monitoring has gained interest over the past decade as they have shown great potential for optimized engine operation with higher efficiency, reduced fuel consumption and maintenance costs. Specifically, sensor coatings containing luminescent ions enable materials monitoring using integrated spectral characteristics. While facilitating sensing capabilities, luminescent rare-earth dopants ideally present minimal intrusiveness for the thermal barrier coating. However, the effects of rare-earth dopant addition on thermomechanical and thermochemical properties remain unclear. Our study intends to fill this knowledge gap by characterizing coatings’ internal thermomechnical properties under realistic gas turbine engine operating temperatures. In this work, TBC configurations including industry standard coatings and sensor coatings were compared to quantify dopant intrusiveness. The TBC configurations have been characterized using high-energy synchrotron X-ray diffraction while being heated up to gas turbine engine temperatures. The TBC samples have been subjected to a single cycle thermal load with multiple ramps and holds during XRD data collection. Depth-resolved XRD was used to obtain the 2D diffraction patterns corresponding to each depth location for the determination of strain distributions along the TBCs. Internal strains and stresses acting through the coatings were quantified mostly highlighting that there is negligible variation between the standard and novel sensor coatings. Thus, the thermal response at high temperature remains unaffected with addition of luminescent dopants. This evaluation of novel coating configurations provides valuable insight for future safe implementation of these temperature sensing coatings without performance reductions.