We investigated composition-dependent catalytic activity of bimetallic PtPd dendrimer-encapsulated nanoparticles (DENs) that had a uniform size of ∼1.7nm for hydrolytic dehydrogenation of ammonia borane (AB). The PtPd DENs, composed of seven different Pt: Pd ratios, were synthesized using hydroxyl-terminated sixth-generation polyamidoamine dendrimers as a molecular template. The dendrimer-templating method allowed for synthesizing bimetallic PtPd DENs with controllable nanoparticle composition while fixing the size of the nanoparticles uniformly at ∼1.7 nm. Compared with monometallic Pt and Pd DENs, the bimetallic PtPd DENs showed superior catalytic activity for the hydrolytic dehydrogenation of AB. Furthermore, the bimetallic PtPd DENs exhibited composition-dependent activity with the maximum activity (i.e., average turnover frequency=108.5±15.9molH2·molatom Pt+pd−1·min−1) at a Pt: Pd ratio of 1:1 for the catalytic hydrolysis of AB.

中文翻译：

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平均尺寸为 1.7 nm 的双金属 PtPd 树枝状大分子包裹纳米粒子的组成依赖性催化活性用于氨硼烷的水解脱氢

我们研究了双金属 PtPd 树枝状聚合物包裹的纳米粒子 (DEN) 的组成依赖性催化活性，该纳米粒子具有约 1.7nm 的均匀尺寸，用于氨硼烷 (AB) 的水解脱氢。PtPd DEN 由七种不同的 Pt:Pd 比率组成，使用端羟基的第六代聚酰胺胺树枝状聚合物作为分子模板合成。树枝状聚合物模板法允许合成具有可控纳米颗粒组成的双金属 PtPd DEN，同时将纳米颗粒的尺寸均匀地固定在~1.7 nm。与单金属 Pt 和 Pd DENs 相比，双金属 PtPd DENs 对 AB 的水解脱氢表现出优异的催化活性。此外，双金属 PtPd DEN 表现出具有最大活性（即平均转换频率 = 108.5±15）的成分依赖性活性。