Phenylalanine Dipeptide-Regulated Ag/In₂O₃ Nanocomposites for Enhanced NO₂ Gas Sensing at Room Temperature with UV Illumination

Abstract

This work demonstrates that phenylalanine dipeptide-regulated silver can improve the gas sensing performance of a nitrogen dioxide (NO 2 ) gas sensor. Herein, Ag/In 2 O 3 was prepared by a hydrothermal method to detect NO 2 gas, where varying amounts of phenylalanine dipeptide (FF) were introduced to regulate the growth of Ag NPs. The morphologies, microstructures, and compositions of the obtained samples were characterized in detail, and the results indicate that Ag NPs grow into nanorods with the regulation of FF. The gas sensing characteristics were systematically investigated with UV illumination (365 nm) at room temperature (25 °C). Upon exposure to NO 2 gas, the optimal sensor exhibits a relatively high response value, good linearity, and satisfactory stability. In addition, the sensor can maintain good gas sensing performance under varying humidity. The reason underlying the observed enhancement in the gas sensing property is the formation of more active sites with the Ag nanorod structure. This study suggests that the introduction of polypeptides is a promising idea to improve the performance of gas sensors.

High-performance UV-activated room temperature NO2 sensors based on TiO2/In2O3 composite

“…14. 52,53 NO 2 captures electrons owing to its oxidizing nature, and consequently, it is adsorbed on the surface of the TiO 2 /In 2 O 3 composite. The optimized TiO 2 /In 2 O 3 heterostructure, with controlled TiO 2 NPs uniformly dispersed inside the In 2 O 3 NFs, provides more active reaction sites to promote the adsorption and desorption of NO 2 molecules.…”

Metal–Organic Framework-Derived LaFeO3@SnO2/Ag p–n Heterojunction Nanostructures for Formaldehyde Detection

“…45 More importantly, the uniformly dispersed Ag nanoparticles on the surface can effectively reduce the surface activation energy, enabling the sensing electrode to efficiently and rapidly dissociate formaldehyde molecules even at lower temperatures. The all-around performance of 0.1LS/Ag is substantially improved compared to 0.1LS nanomaterials without Ag modification, 46 as shown in Figure S5. (II) The generation of a heterojunction between Ag 2 O and SnO 2 .…”

Anl-proline-modified chiral porous hyper-crosslinkedl-phenylalanine dipeptide—increased reaction rate and selectivity in asymmetric catalysis

“…26 Moreover, a heterogeneous catalyst based on HCPs can easily be recycled and reused, 27,28 making it a suitable structure for synthesizing heterogeneous catalyst supports. 29 L-Phe-L-Phe-OMe has fewer substituents on its surface and is structurally stable at high temperatures, 30 which facilitates the formation of HCPs with stable chiral structures in the hyper-crosslinking reaction. In addition, the dipeptide structure will form holes with a special chiral environment after hyper-crosslinking, which is conducive to improving the enantioselectivity of the products.…”