基于铁酸镧/氧化锌异质结纳米材料的薄膜型二氧化碳传感器OA

To address the bottlenecks of high operating temperature and slow response/recovery kinetics of metal oxide semiconductor-based carbon dioxide(CO2)sensors,lanthanum ferrite/zinc oxide(LaFeO3/ZnO)nanocomposites were fabricated via a hydrothermal-sol-gel composite process and coated onto ceramic tubes to construct CO2 sensors.X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)analyses confirmed the microstructure and elemental chemical states of the materials.The as-constructed sensor exhibited a response of 3.15 toward 1080 mg/m3 CO2 at room temperature((25±2)℃)with response/recovery time of 8.2 s and 11.4 s,respectively,demonstrating excellent selectivity,cycling stability,and quantitative accuracy.Density functional theory(DFT)calculations revealed the room-temperature gas-sensing enhancement mechanism:the LaFeO3/ZnO p-n heterojunction generated a built-in electric field at the interface that effectively promotes carrier separation;oxygen vacancies and basic sites on the LaFeO3 surface enhanced the preferential chemisorption of CO2;and the elevated conduction band density of states facilitated electron transition and increased the free carrier concentration.These synergistic effects endowed the sensor with stable CO2 detection capability at room temperature,offering new material strategies and theoretical support for the design of high-performance room-temperature CO2 sensors.