Reusable macroporous photonic crystal-based ethanol vapor detectors by doctor blade coating

Highly sensitive volatile organic compounds vapour measurements using a long period grating optical fibre sensor coated with metal organic framework ZIF-8

“…There have been a number of fibre-optic based ethanol gas sensors proposed recently using the deposition of the sensitive layer on the fibre tip to form Fabry-Perot interferometers [14][15][16][17][18] or evanescent wave sensors, where part of the cladding is mechanically or chemically removed and then the functional coating is deposited over the stripped region [11,[19][20][21][22]. A coating sensitive to ethanol vapours has been also applied on the surface of a photonic crystal fibre [23], long period grating (LPG) [24] or quartz crystal microbalance (QCM). The properties of pub- n/a n/a [11] Cladding removed PMMA optical fibre in intensity at selected wavelengths Sm2O3 0 to 500 ppm 76 × 10 −3 au/ppm 78 min n/a [20] Cladding removed PMMA optical fibre in intensity at selected wavelengths Graphene oxide 100 to 500 ppm 0.26 a.u./ppm n/a n/a [21] Cladding removed silica optical fibre in power at selected wavelength Max shift of 59 nm/pure EtOH gas n/a n/a [23] lished ethanol gas fibre optic based sensors (and one example of a QCM) are summarized in Table 1.…”

“…A coating sensitive to ethanol vapours has been also applied on the surface of a photonic crystal fibre [23], long period grating (LPG) [24] or quartz crystal microbalance (QCM). The properties of pub- n/a n/a [11] Cladding removed PMMA optical fibre in intensity at selected wavelengths Sm2O3 0 to 500 ppm 76 × 10 −3 au/ppm 78 min n/a [20] Cladding removed PMMA optical fibre in intensity at selected wavelengths Graphene oxide 100 to 500 ppm 0.26 a.u./ppm n/a n/a [21] Cladding removed silica optical fibre in power at selected wavelength Max shift of 59 nm/pure EtOH gas n/a n/a [23] lished ethanol gas fibre optic based sensors (and one example of a QCM) are summarized in Table 1. Reported sensors suffer mostly from a high response time in a range of 10 s min [19,24] and are usually tested over a limited concentration range.…”

“…Reported sensors suffer mostly from a high response time in a range of 10 s min [19,24] and are usually tested over a limited concentration range. For example, they are tested at saturated vapour conditions [18,24], high (in a range of thousands of ppm) [22,23,26] or low level concentrations usually below 500 ppm [11,14,[19][20][21]. The comparison in sensitivity shown in Table 1 is limited as only two papers show the limit of detection of 2.74 [16] and 380 ppm [17].…”

Bioinspired Stimuli‐Responsive Color‐Changing Systems

“…Using a different fabrication approach, a scalable and roll‐to‐roll compatible doctor‐blade technology has been employed to prepare a reversible vapor detector based on macroporous poly(ethoxylated trimethylolpropane triacrylate) (PETPTA) films . They have used monodispersed silica colloids (225 nm in size) as a template, which are then etched away and result in the macroporous polymer film.…”

UV and blue-light anti-reflective structurally colored contact lenses based on a copolymer hydrogel with amorphous array nanostructures

“…where n silica ¼ 1.42 (ref. 25) and n hydrogel ¼ 1.43. 22 In this case, n eff ¼ 1.427 for sample C (f silica ¼ 30%).…”