In the present study, gas sensors based on Pd-loaded WO₃ sensor layers were prepared and coated with zeolite films to improve the selectivity. The sensing behavior of such sensors was characterized using different single gases and mixtures to assess their selectivity. We observed that the selectivity of sensors based on Pd-WO₃ can be significantly tailored towards specific target gases by adding a printed zeolite film. The use of an HZSM-5 zeolite film made the Pd-loaded WO₃ sensor highly sensitive to CO, with a response of around 10 at 100 ppm CO. When Pt-modified HZSM-5 zeolite film was used, same sensor became sensitive to methanol, with a detection limit of 0.5 ppm even in the presence of high concentration of CO. Interestingly, the Pt-modified HZSM-5 film caused the catalytic conversion of CO, which resulted in a p-type response to CO. In addition, in the presence of methanol such a p-type response to CO was also observed in pure WO₃ sensor. Based on the power-law response to oxygen, it is proposed that the resistive responses of all tested sensors were highly dependent on the oxygen content, indicating that oxygen adsorbates on the surface were involved in the fundamental sensing mechanism, which is the same process as conventional gas sensors. The present study showed that the configuration of Pd-WO₃ sensing layers coated with zeolite films is viable for tailoring the selectivity of gas sensors.

在本研究中，制备了基于载有Pd的WO ₃传感器层的气体传感器，并用沸石膜覆盖以提高选择性。使用不同的单一气体和混合物来评估此类传感器的感测行为，以评估其选择性。我们观察到，通过添加印刷的沸石膜，可以显着地针对特定目标气体调整基于Pd-WO ₃的传感器的选择性。使用HZSM-5沸石薄膜制成了Pd负载的WO ₃对CO高度敏感的传感器，在100 ppm CO时响应约为10。当使用Pt改性的HZSM-5分子筛膜时，同一传感器对甲醇变得敏感，即使存在高浓度，其检测限为0.5 ppm有趣的是，Pt修饰的HZSM-5膜引起了CO的催化转化，从而导致了对CO的p型响应。此外，在甲醇存在下，还观察到了对CO的p型响应。在纯WO _3中传感器。根据对氧气的幂律响应，建议所有测试传感器的电阻响应都高度依赖于氧气含量，这表明表面上吸附的氧气参与了基本传感机制，这与检测过程相同。传统的气体传感器。本研究表明，涂有沸石膜的Pd-WO ₃传感层的构型对于调整气体传感器的选择性是可行的。