Triethylamine (TEA) poses significant risks to both environmental quality and human health. Hence, in this work, we employed an ionic-inserted MOF-derived method to synthesize Nd2O2CO3-based nanocomposites. Electronic structure modulations of Nd2O2CO3 from approximate insulators into semiconductors were realized by In3+ intercalations, which profoundly reduces bandgap and facilitates electron transferring. Adequate oxygen vacancies and Lewis acidity sites in Nd2O2CO3 provide more active sites for TEA reactions. Leveraging defect engineering and electronic structure modulation, the optimized sensor exhibited a considerable TEA response (167.94), rapid responding/recovering (5/42 s) at low temperature (160 ℃). Furthermore, the intensive CO2 adsorption capabilities of Nd2O2CO3 and the abilities to react between TEA and CO2 were confirmed by In-situ DRIFTS thereby certificating the availability of sensors in an atmospheric environment with exceptional anti-interference capability. This work not only develops novel TEA sensing materials but also proposes feasible strategies for optimizing TEA sensing characteristics through ion intercalation.