Polycrystalline In₂O₃ modified with CdIn₂S₄ for enhanced triethylamine gas detection

A novel low-power and highly selective triethylamine gas-sensitive material was created by building a hierarchical structure and mixed-phase In₂O₃, then joining it with CdIn₂S₄ rich in cationic acid sites to form a heterojunction. Gas sensitivity tests reveal that the CdIn₂S₄-In₂O₃-based sensor has a faster response/recovery speed (1 s/88 s) and a response value of 29.8 to 10 ppm triethylamine gas at an optimal working temperature (60 °C), which is 2.9 times the response value of the unmodified In₂O₃ sensor. Furthermore, the detection limit has reached the ppb level (100 ppb with a SNR of 3.2). As demonstrated by the experiment, the two-dimensional material and layered structure cooperate to improve the sensitive material's response site and hasten the adsorption and surface release of triethylamine molecules. Furthermore, by interfacial electrical modulation, the hierarchical heterostructure efficiently increases the material's adsorption capability to triethylamine molecules. The sensor maintains excellent response sensitivity while greatly enhancing the selective recognition performance of triethylamine gas when combined with the synergistic impact of the acidic active site supplied by CdIn₂S₄.