Abstract Heating PdAu nanoparticles deposited on silica in hydrogen results in palladium silicide(s) formation. The degree of palladium extraction by silicon species (ex-silica) is conversely correlated with the gold content in the PdAu alloys. In addition, the phase changes are less extensive than analogous transformations in a previously investigated PdCu-silica composite. Very high temperatures (>550 °C) are required to initiate the transformation of PdAu-SiO2 into respective bulk metal silicide(s), whereas for the PdCu-SiO2 (and Pd-SiO2) similar changes have already been observed at ≤450 °C. Based on existing literature data, it is considered that the reason for this difference is a relative availability of palladium-rich material at the Pd-IB alloy-silica phase boundary. In the case of PdAu, the segregation of gold at the surface is very pronounced, making this alloy more resistant against Pd extraction required for the silicide formation.

中文翻译：

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PdAu-SiO 2 纳米复合材料在氢气中加热时生成硅化钯

摘要 在氢气中加热沉积在二氧化硅上的 PdAu 纳米粒子会形成钯硅化物。硅物质（ex-silica）提取钯的程度与 PdAu 合金中的金含量成反比。此外，相变不如先前研究的 PdCu-二氧化硅复合材料中的类似转变广泛。需要非常高的温度 (> 550 °C) 来启动 PdAu-SiO2 转化为相应的块状金属硅化物，而对于 PdCu-SiO2（和 Pd-SiO2），在≤450 ° 时已经观察到类似的变化C。根据现有的文献数据，认为这种差异的原因是在 Pd-IB 合金-二氧化硅相界处富钯材料的相对可用性。在 PdAu 的情况下，