Room‐temperature ferroelectric K₂W₇O₂₂ (KWO) nanorods as a sensor material for the detection of acetone

Abstract

Acetone has been shown to be a biomarker for diagnosing and monitoring diabetes. The newly synthesized K2W7O22 (KWO) nanorods show a sensitive response to acetone at room temperature. This promising sensing performance could provide an optimal way to design an easy‐to‐use breathalyzer device for both personal and clinical use to monitor blood glucose levels non‐invasively. The preliminary results indicate that such good response is mainly due to the strong room temperature ferroelectric property of KWO, which has been controlled for the first time by optimizing the temperature for hydrothermal growth. The study of the relationship between material structure and properties indicates that the material is a single crystal with potassium atoms replacing the tungsten causing the ferroelectric property to emerge. The porous structure with a specific surface facet (002) exhibits good sensitivity and selectively for detection of acetone. The unique structure and material properties of as‐synthesized K2W7O22 allow it to effectively interact with acetone. The preliminary results reveal that the sensing performance of K2W7O22 can be further improved by tuning its crystal structure.

KxWO Is a Novel Ferroelectric Nanomaterial for Application as a Room Temperature Acetone Sensor

“…Figure 2 shows the Raman obtained of different K x WO samples grown (a) with L-121, and (b) with a change in potassium content. Comparing K 1.8 WO, and K 2.0 WO when grown with L-121, we see little difference other than a more prominent ferroelectric phase observed by farther shouldering, which was previously reported by our group [25]. In detail, there are two primary peaks at 715 cm −1 and 805 cm −1 in Raman spectra, which indicate the presence of the γ-phase.…”

“…With the addition of L-121, as shown in Figure 2a, a decrease of peaks related to the γ-phase was seen in K 1.8 WO-L121 and K 2.0 WO-L121. Instead, one primary peak below 800 cm −1 was present, which indicates a further shift to the ε-phase [15,25]. This result combined with the XRD data indicate KWO grown with L-121 has a stronger ferroelectric phase as well as a higher ratio of the (002) facet.…”

“…85-2460. It can be tuned for higher acetone sensitivity by adjusting the growth temperature [14,16,25]. It has been reported that the controlled exposure of the crystal facets of WO 3 have a high impact on acetone sensitivity and selectivity [14].…”

Two-Dimensional Ti3C2 MXene-Based Novel Nanocomposites for Breath Sensors for Early Detection of Diabetes Mellitus

“…A precursor solution is made from di-H 2 O, oxalic acid dehydrate (>99%, VWR, Radnor, PA, USA), K 2 SO 4 (>99%, VWR, Radnor, PA, USA), Na 2 WO 4 •2H 2 O (95%, Alfa Aesar, Tewksbury, MA, USA), and hydrochloric acid (36-38%, Aqua Solutions Inc., Deer Park, TX, USA). The solution is heated in a 30 mL autoclave at 225 • C for 24 h. The resulting product is KWO nanowires [18][19][20][21].…”

“…In our previous study [16][17][18][19][20][21][22][23], 1-dimensional (1D) nanowires, K 2 W 7 O 22 (KWO), were successfully synthesized and showed unique room-temperature ferroelectric properties which caused strong attraction towards polar gases, such as acetone, due to a strong charge transfer between acetone and ferroelectric KWO. The KWO nanomaterial also has a large surface to volume ratio due to the nanowire structure [22].…”