Enhanced NH3 sensing performance at ppb level derived from Ti3C2T -supported ZnTi-LDHs nanocomposite with similar metal-semiconductor heterostructure

Moisture-Resistant Gas Sensor Derived from ZIF-8/Layered Double Hydroxide/Ti3C2Tx Nanocomposites for Trace Isopropanol Detection

“…MXenes have been recently reported to be a novel candidate for substrates due to their tailored surface chemistry. , As the most studied material in the MXene family, Ti 3 C 2 T x has been extensively used in the field of gas/humidity sensors owing to its large specific surface and metallic conductivity. − Hence, Ti 3 C 2 T x is a good choice to solve the stacking problem of LDHs for boosting the gas-sensing performance. As for our previous research, LDHs/Ti 3 C 2 T x was successfully prepared and the corresponding sensor was revealed to show a better performance than LDHs . Nevertheless, the active adsorption sites of LDHs/Ti 3 C 2 T x nanocomposites are still partially restricted due to the face-to-face stacking of LDHs and Ti 3 C 2 T x caused by electrostatic interaction.…”

“…Nevertheless, the active sites of LDHs for gas adsorption are significantly reduced due to their inevitable face-to-face stacking, which severely hinders the application of LDHs in high-sensitivity sensors . In order to improve the stacking of LDHs, researchers started to study the directed growth of LDHs on other 2D substrate materials, such as graphene and MXene . MXenes have been recently reported to be a novel candidate for substrates due to their tailored surface chemistry. , As the most studied material in the MXene family, Ti 3 C 2 T x has been extensively used in the field of gas/humidity sensors owing to its large specific surface and metallic conductivity. − Hence, Ti 3 C 2 T x is a good choice to solve the stacking problem of LDHs for boosting the gas-sensing performance.…”

Synergistic enhanced NH3-sensing of SnS via Ti3C2Tx-oriented vertical growth and oxygen-containing functional group regulation

“…7(c), both sensors show a much higher response value towards NH 3 in contrast to the other gases. Here, we define the selectivity ( k ) to NH 3 gas with respect to other interfering gases as follows: 45 k = S gas / S NH 3 where S NH 3 and S gas are the response values towards NH 3 gas and towards certain interfering gas, respectively. The calculated k values of ST-40 are 0.080, 0.073, 0.004, 0.029, 0.204, and 0.002, while the values of OST-40 are 0.009, 0.026, 0.053, 0.178, and 0.001, respectively.…”

“…The sensor was recovered by opening the top cover of the test chamber and setting up the electric blower fixed at the bottom of the chamber. The calculation formula for the conversion between the concentration of the target gas and the volume of the liquid is as follows: 45 where C (ppm) is the concentration of the target gas, ρ (g mL −1 ), D and M (g mol −1 ) are the density, purity, molecular weight of the liquid, respectively, and V 1 (L) and V 2 (L) are the volumes of the liquid introduced and the test chamber, respectively.…”

“…19 The sensing mechanism of the sensor based on the SnS/Ti 3 C 2 T x heterojunction is similar to that of the sensor based on a traditional metal oxide semiconductor, which depends on the effective absorption/desorption of gas molecules on the sensing surface and the subsequent redox reaction. 57 Consequently, the NH 3 sensing process involves the following reactions: 45 NH 3 (gas) ↔ NH 3 (ads)4NH 3 (ads) + 5O 2 − ↔ 4NO(ads) + 6H 2 O(ads) + 5e − …”