论文标题
钯及其合金中对氢化的阳性抗性反应
Positive versus negative resistance response to hydrogenation in palladium and its alloys
论文作者
论文摘要
电阻固态传感器广泛用于多种应用，包括分子和气体检测。靶物质的吸收或插入会改变晶格参数和薄膜的有效厚度，薄膜通常在分析其运输特性的一般且尤其是传感器响应时被忽略。在这里，我们探索了吸收氢的基于钯的薄膜的情况，并证明厚度的膨胀是确定高电阻率膜中抗性反应的幅度和极性的重要机制。在三个具有可变电阻率的基于PD的系统中，测试并确认了对厚度的修改的电阻响应模型：渗透阈值上方和下方的薄PD膜，厚的PD-SIO2颗粒颗粒复合膜，具有不同的硅胶含量，二氧化硅含量不同，PD富含PD的COPD合金在其中电阻率取决于CO浓度。由于氢化物的形成和由于厚度膨胀而引起的膜电阻降低引起的叠加电阻率的叠加提供了对具有不同结构和组成的连续和不连续膜中氢化响应的一致性。
Resistive solid state sensors are widely used in multiple applications, including molecular and gas detection. Absorption or intercalation of the target species varies the lattice parameters and an effective thickness of thin films, which is usually neglected in analyzing their transport properties in general and the sensor response in particular. Here, we explore the case of palladium-based thin films absorbing hydrogen and demonstrate that expansion of thickness is an important mechanism determining the magnitude and the very polarity of the resistance response to hydrogenation in high resistivity films. The model of the resistance response that takes into account modifications of thickness was tested and confirmed in three Pd-based systems with variable resistivity: thin Pd films above and below the percolation threshold, thick Pd-SiO2 granular composite films with different content of silica, and Pd-rich CoPd alloys where resistivity depends on Co concentration. Superposition of the bulk resistivity increase due to hydride formation and decrease of film resistance due to thickness expansion provides a consistent explanation of the hydrogenation response in both continuous and discontinuous films with different structures and compositions.
