以RuCl 3和NH 4 ReO 4为前体盐，以乙二醇为还原剂，通过微波辅助多元醇法成功合成了均匀的RuRe双金属纳米颗粒（RuRe NPs）。所获得的材料通过紫外可见光谱，透射电镜，SEM-EDS，XRD和XPS光谱进行了表征。TEM表征表明，使用聚N合成微波多元醇-乙烯基-2-吡咯烷酮（PVP）作为封端剂导致标称Ru / Re原子比分别为75:25和50:50的球形RuRe NP的平均尺寸分别为1.4 nm或1.6 nm窄的粒度分布（0.5-2.5 nm）。双金属NP的大小略高于通过相同方法制备的单金属Ru（PVP）NP（1.3 nm）。XRD数据证实了所得产物的尺寸小。无需添加PVP即可进行γ-氧化铝或二氧化硅沉积的NP的“原位”合成，这也导致了双金属RuRe NP的形成。XPS分析证实，所支持的RuRe NP由Ru 0，Re 0组成和氧化的Ru和Re物种。然而，所制备的双金属NP的平均尺寸和尺寸分布在很大程度上取决于所用载体的类型。在的情况下的γ-Al 2 ö 3获得了窄的粒径分布（0.5-5 nm），RuRe和Ru NP的平均粒径比PVP稳定的NP略高。所制备的二氧化硅沉积的RuRe或Ru NPs分散不充分，并且通过TEM观察到NPs的大量聚集。但是，衍射数据表明，大的团聚体由小的双金属RuRe NPs（2.6 nm）或非金属Ru NPs（9 nm）组成。由于与二氧化硅表面的相互作用较弱，这些很小的RuRe NP彼此非常靠近，因此在400°C的氢气处理过程中很容易烧结。与此相反，双金属纳米粒子RuRe沉积在γ-Al系2 ö 3在相似的还原条件下非常稳定，对氢的化学吸附活性很高。初步催化数据表明，在丙烷氧化反应中，氧化铝沉积的RuRe纳米催化剂比Ru纳米催化剂更具活性。
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Microwave-assisted polyol synthesis of bimetallic RuRe nanoparticles stabilized by PVP or oxide supports (γ-alumina and silica)
Uniform RuRe bimetallic nanoparticles (RuRe NPs) were successfully synthesized by a microwave-assisted polyol method using RuCl3 and NH4ReO4 as a precursor salts and ethylene glycol as a reducing agent. The obtained materials were characterized by UV–vis, TEM, SEM-EDS, XRD and XPS spectroscopy. Characterization by TEM showed that microwave-polyol synthesis using poly-N-vinyl-2-pyrrolidone (PVP) as a capping agent led to spherical RuRe NPs with mean size of 1.4 nm or 1.6 nm for the NPs with the nominal Ru/Re atomic ratio of 75:25 and 50:50, respectively, and a narrow particle size distributions (0.5–2.5 nm). The size of the bimetallic NPs was slightly higher than monometallic Ru(PVP) NPs (1.3 nm) prepared by the same method. XRD data confirmed small size of the obtained products. The “in situ” synthesis of γ-alumina or silica deposited NPs has been carried out without the addition of PVP, leading also to formation of bimetallic RuRe NPs. XPS analysis confirmed that the supported RuRe NPs consisted of Ru0, Re0 and oxidized Ru and Re species. However, the mean sizes and size distributions of the as-prepared bimetallic NPs depend greatly on the kind of the support used. In the case of γ-Al2O3 a narrow particle size distributions (0.5–5 nm) were obtained and the mean sizes of RuRe and Ru NPs were slightly higher then for the PVP-stabilized NPs. The as-prepared silica deposited RuRe or Ru NPs were not well-dispersed and large aggregation of NPs was observed by TEM. However, diffraction data show that large agglomerates were composed from small bimetallic RuRe NPs (2.6 nm) or nomometallic Ru NPs (9 nm). Due to the weak interaction with silica surface, these small RuRe NPs lying very close to each other, were easily sintered during the hydrogen treatment at 400 °C. In contrast, the bimetallic RuRe NPs deposited on the γ-Al2O3 under similar reducing conditions were very stable and have high activity for hydrogen chemisorption. Preliminary catalytic data show that alumina deposited RuRe nano-catalysts were more active then Ru nano-catalyst in the propane oxidation reaction.
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