金属—载体强相互作用（SMSI）对Pd／ZnO半导体陶瓷气敏特性的作用

本文借助XRD,红外光谱等分析手段,研究了金属-载体相互作用状态对Pd/ZnO半导体陶瓷气敏特性的影响,据此提出贵金属催化剂和半导体陶瓷在气敏特性中的共同作用机理。PdZn界面层是氢处理时半导体正离子和金属原子间的相互扩散及反应所致。可以认为金属-载体间的强相互作用(SMSI)能显著提高其气敏特性。

SMSI EFFECT ON GAS SENSITIVE CHARACTERISTIC OF SEMICONDUCTING Pd/ZnO CERAMICS

By the aid of X-ray diffraction and infrared spectrum, the influence of interaction between metal and support on the gas sensitive characteristics of semiconducting Pd/ZnO ceramics was studied. Based on the study, the interaction mechanism of noble metal catalyst and semiconducting ceramics in the gas sensitive action is proposed. A new interfacial phase(PdZn) may be formed as a result of inter-diffusion and reaction between semiconductor cations and metal atoms during hydrogen treatment. It is suggested that the strong metal support interaction(SMSI) would facilitate the charge transfer between Pd and ZnO and create an active structure for oxygen absorption and shift redox reaction,therefore the gas sensitivity of Pd/ZnO semiconducting ceramics would be obviously enhanced.