High selectivity for room temperature detection of ammonia via in-situ Raman spectroscopy based on Pt quantum dots modified WS2 nanosheets

Pt and black phosphorus co-modified flower-like WS2 composites for fast NO2 gas detection at low temperature

“…The diffraction peaks at approximately 16.98°, 26.54°, 34.23°, 34.97°, and 52.35°are assigned to the BP (020), ( 021), ( 040 , which is very similar to the XRD results of Pt quantum dot-modified WS 2 nanosheets. 9 It is also found that the X-ray diffraction intensity of WS 2 is significantly weakened by incorporating BP and Pt, as shown in Fig. 3b.…”

“…It is expected that the rate of surface reaction can be further enhanced by spill-over effects, thus yielding a better gas sensitivity. 6,9,27 The optimal working temperature is also 50 °C for the WS 2 /Pt and BP-WS 2 /Pt sensors towards 8 ppm NO 2 , as shown in Fig. 8(a) and (b).…”

“…So far, various feasible strategies, e.g., constructing composites, 4,8 noble metal functionalization, 6,[9][10][11] building heterojunctions, [12][13][14][15][16] and UV-light irradiation, 15,17,18 have been tried to overcome these barriers and simultaneously realize low-temperature detection. For example, the gas-sensing properties of pristine WS 2 have been significantly improved by fabricating WS 2 /CNF composites using a hydrothermal method.…”

In Situ Raman Study of Voltage Tolerance Up to 2.2 V of Ionic Liquid Analogue Supercapacitor Electrolytes Immune to Water Adsorption Conferred by Amphoteric Imidazole Additives

“…ILA 4:1 Raman spectral signals in the high-wavenumber region (500−3520 cm −1 ) show little variation with applied potential, with or without addition of IMZ; in the low-wavenumber region (200−500 cm −1 ), they show a regular evolution with an increase in potential (Figure 5a). 41 For ILA 4:1 , the strength of two peaks (at 197 and 265 cm −1 ) corresponding to the bending vibration It is important to note that, contrary to the trend of ILA 4:1 , the intensity of the two peaks at 197 and 265 cm −1 for ILA 4:1 −2 wt % IMZ increases almost linearly when the potential increases from 0.2 to 0.7 V (the bottom portion of Figure 5b), 51,52 suggesting that the addition of amphoteric IMZ induces a redistributive equilibrium or polarity reversal of the PDO H-bonding network in the solvent shell (Figure 5c). Because of the high electronegativity of N in IMZ molecules, it can induce the reversal or rearrangement of the polar C−C−O skeleton in PDO.…”

“…It is important to note that, contrary to the trend of ILA 4:1 , the intensity of the two peaks at 197 and 265 cm –1 for ILA 4:1 −2 wt % IMZ increases almost linearly when the potential increases from 0.2 to 0.7 V (the bottom portion of Figure b), , suggesting that the addition of amphoteric IMZ induces a redistributive equilibrium or polarity reversal of the PDO H-bonding network in the solvent shell (Figure c). Because of the high electronegativity of N in IMZ molecules, it can induce the reversal or rearrangement of the polar C–C–O skeleton in PDO.…”