Belykh Lyudmila B, Skripov Nikita I, Sterenchuk Tatyana P, Kilesnikov Sergey S, Schmidt Fedor K
J Nanosci Nanotechnol. 2017 Jan;17(1):696-704. doi: 10.1166/jnn.2017.12606.
Size and phase composition of the Pd-P catalyst, which is highly active in the hydrogenation of unsaturated compounds have been established using X-ray powder diffraction (XRD) analysis, high resolution transmission electron microscopy (HRTEM) technique in combination with energy-dispersive X-ray (EDX) analysis and selected area electron diffraction (SAED) analysis. The reduction of Pd(acac)₂ with hydrogen in the presence of white phosphorus (P/Pd = 0.3) in N,N-dimethylformamide (DMF) at 80 °C results in formation of Pd-enriched polycrystalline nanoparticles with a predominant diameter of 5.7 nm (C(Pd) = 1 mmol·L⁻¹) and 5.1 nm (C( Pd) = 5 mmol · L⁻¹). The polycrystallites consist of palladium phosphides (Pd5P2, Pd3P0.8 and palladium crystallites. It is found that phase composition of the Pd-P catalyst is changed at the stage of Pd-P sample preparation for XRD analysis. It is established that palladium phosphide Pd6P detected by XRD technique is a product of the solid-phase reaction between Pd crystallites and Pd₅P₂, Pd₃P(0.8) palladium phosphides at the stage of high-temperature sample preparation (400 °C). The mechanism of low-temperature synthesis of palladium phosphides was proposed.
通过X射线粉末衍射（XRD）分析、高分辨率透射电子显微镜（HRTEM）技术结合能量色散X射线（EDX）分析和选区电子衍射（SAED）分析，确定了在不饱和化合物氢化反应中具有高活性的Pd-P催化剂的尺寸和相组成。在80℃下，于N，N-二甲基甲酰胺（DMF）中，在白磷存在下（P/Pd = 0.3）用氢气还原Pd(acac)₂，生成主要直径为5.7 nm（C(Pd) = 1 mmol·L⁻¹）和5.1 nm（C(Pd) = 5 mmol·L⁻¹）的富钯多晶纳米颗粒。这些多晶体由磷化钯（Pd5P2、Pd3P0.8）和钯微晶组成。发现Pd-P催化剂的相组成在用于XRD分析的Pd-P样品制备阶段发生变化。已确定通过XRD技术检测到的磷化钯Pd6P是在高温样品制备（400℃）阶段，Pd微晶与Pd₅P₂、Pd₃P(0.8)磷化钯之间固相反应的产物。提出了低温合成磷化钯的机理。
