Methyl(—CH3)-terminated ZnO Nanowires for Selective Acetone Detection: Novel Approach Toward the Sensing Performance Enhancement Via Self-Assembly Molecules

The inspiration behind this work is to show the importance to tailor metal oxides (MOX’s) nanowires with suitable self-assembled monolayers (SAM’s) for the development of highly efficient, selective, and low...

Flexible silicon nanowires sensor for acetone detection on plastic substrates

Acetone commonly exists in daily life and is harmful to human health, therefore the convenient and sensitive monitoring of acetone is highly desired. In addition, flexible sensors have the advantages of light-weight, conformal attachable to irregular shapes, etc. In this study, we fabricated high performance flexible silicon nanowires (SiNWs) sensor for acetone detection by transferring the monocrystalline Si film and metal-assisted chemical etching method on polyethylene terephthalate (PET). The SiNWs sensor enabled detection of gaseous acetone with a concentration as low as 0.1 parts per million (ppm) at flat and bending states. The flexible SiNWs sensor was compatible with the CMOS process and exhibited good sensitivity, selectivity and repeatability for acetone detection at room temperature. The flexible sensor showed performance improvement under mechanical bending condition and the underlying mechanism was discussed. The results demonstrated the good potential of the flexible SiNWs sensor for the applications of wearable devices in environmental safety, food quality, and healthcare.

A facile method for preparation of porous nitrogen-doped Ti Ti3C2Tx MXene for highly responsive acetone detection at high temperature

Porous nitrogen-doped Ti3C2T[Formula: see text] MXene (N-TCT) with a three-dimensional network structure is synthesized via a simple sacrifice template method and then utilized as an acetone gas sensor. By introducing nitrogen atoms as heteroatoms into Ti3C2T[Formula: see text] nanosheets, some defects generate around the doped nitrogen atoms, which can greatly improve the surface hydrophilicity and adsorption capacity of Ti3C2T[Formula: see text] Mxene nanosheets. It resulted in the enhanced gas sensitivity, achieving a response value of about 36 ([Formula: see text]/[Formula: see text] × 100%) and excellent recovery time (9s) at 150[Formula: see text]C. Compared with the pure Ti3C2T[Formula: see text]-based gas sensor (381/92s), the response and recovery time are both obviously improved, and the response value increased by 3.5 times. The gas-sensing mechanism of the porous N-TCT is also discussed in detail. Based on the excellent gas sensitivity of porous N-TCT for highly responsive acetone detection at high temperatures, the strategy of nitrogen-doped two-dimensional nanomaterials can be extended to other nanomaterials to realize their potential applications.

0D Zn-ZIF/2D Co-ZIF Derived 0D ZnO/2D Co3O4 Heterostructures for ppb-Level Acetone Detection

Detecting acetone is meaningful in industrial processes and medical fields. Herein, 0D Zn-ZIF/2D Co-ZIF derived 0D ZnO/2D Co3O4 heterostructures are originally designed to improve acetone sensing properties. It is found that when the temperature is 250 °C, the 0D ZnO/2D Co3O4 possesses the highest response (4.73) to 5 ppm acetone, which is about three times more than that of pure 0D ZnO and pure 2D Co3O4. The detection limit of 0D ZnO/2D Co3O4 sensor could be as low as 100 ppb. The response/recovery time of 0D ZnO/2D Co3O4 sensor to 100 ppm acetone is only 3 s/15 s. It is demonstrated that with the introduction of 0D ZnO, the stacking of 2D Co3O4 nanosheets is inhibited and p-n heterojunctions are formed, which could significantly enhance acetone sensing performance.