Modification of nanostructures using metal nanoparticles is an efficient strategy for enhancing the performance of gas sensing. In this paper, a VO₂@Pd nanowires gas sensor was synthesized using a combination of hydrothermal and annealing methods. The content of Pd in the as-prepared products was successfully controlled by adjusting the reaction parameters. The morphology and formation mechanism of VO₂ nanostructures were systematically evaluated. The response value of VO₂@Pd nanowires is 31.94 towards 5 ppm of NO₂, which is about 38.75% higher than that of pristine VO₂ at a relatively low temperature of 50°C. Furthermore, the sensor exhibits good selectivity, excellent response/recovery time, and superior stability towards NO₂. The significant enhancement of NO₂ sensing performance could be attributed to the electronic and chemical sensitization. Density functional theory (DFT) simulation suggests that both the adsorption energy and electron transfer between the VO₂@Pd substrate and NO₂ molecules are optimized synergistically, leading to the improved sensitivity of the gas sensor. Importantly, the strong orbital hybridization between the NO₂ molecule and Pd atom is observed according to density of states (DOS), which is beneficial in selectively improving the NO₂ sensing performance of the VO₂@Pd gas sensor.

使用金属纳米粒子修饰纳米结构是增强气体传感性能的有效策略。本文采用水热法和退火法相结合的方法合成了VO _{2 @Pd纳米线气体传感器。}通过调节反应参数成功控制了所制备产物中Pd的含量。系统评价了VO ₂纳米结构的形貌和形成机制。_{VO 2} @Pd纳米线对5 ppm NO ₂的响应值为31.94，在50°C的相对低温下比原始VO _{2高约38.75%。}此外，该传感器表现出良好的选择性、优异的响应/恢复时间以及对NO ₂的优异稳定性。_{NO 2}传感性能的显着增强可归因于电子和化学敏化。密度泛函理论（DFT）模拟表明，VO ₂ @Pd 基底与NO ₂分子之间的吸附能和电子转移得到协同优化，从而提高了气体传感器的灵敏度。重要的是，根据态密度（DOS）观察到NO _{2分子与Pd原子之间的强轨道杂化，这有利于选择性提高VO 2} @Pd气体传感器的NO ₂传感性能。