Sensors · 2011 · 56 citations · 19 references
Natural SciencesMaterials EngineeringMaterials ScienceAnalytical ChemistrySensorsSpectroscopyAbsorption SpectroscopyChemical SensorsGas SensorsOptical SensingOptical SensorsOptical SpectroscopyAmmonia DetectionChemical Optical SensorsGas SensingMesoporous MaterialsMesoporous NanomaterialsOptical AbsorptionOptical Chemical SensingResponse Time
A meso-structured Al-MCM-41 material was impregnated with bromocresol green (BG) dye and then incorporated into a UV-Vis DRA spectroscopic instrument for the online detection of ammonia gas. The absorption response of the Al-MCM-41/BG ammonia sensing material was very sensitive at the optical absorption wavelength of 630 nm. A high linear correlation was achieved for ppmv and sub-ppmv levels of ammonia gas. The response time for the quantitative detection of ammonia gas concentrations ranging from 0.25 to 2.0 ppmv was only a few minutes. The lower detection limit achieved was 0.185 ppmv. The color change process was fully reversible during tens of cycling tests. These features together make this mesoporous Al-MCM-41 material very promising for optical sensing applications.
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Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism
Charles T. Kresge, M. E. Leonowicz, Wiesław J. Roth et al. · Nature · 1992 · 16.1K citations
Acidity and active sites of Al-MCM-41
H. Kosslick, G. Lischke, B. Parlitz et al. · Applied Catalysis A General · 1999 · 160 citations