Tuning the size of intermetallic nanocrystals is challenging due to the conflicting effects of surface free energy and surface diffusion on the disorder-to-order phase transition during wet-chemistry growth. Herein, we synthesized intermetallic PdCd nanocubes with tunable sizes ranging from 8 to 15 nm by adjusting the Cd precursor concentrations using a wet-chemistry approach. This process shares a mechanism of size tuning similar to quantum dot synthesis, involving the regulation of monomer concentration determined by the precursor concentrations. The intermetallic PdCd nanocubes exhibit distinct size-dependent optical properties compared to platinum group metal nanocrystals of similar size ranges, with increased light-induced catalytic enhancement as size increases. The 15 nm-sized nanocubes exhibited the most significant light-induced catalytic enhancement, reaching 3.3 times, while the 8 nm-sized nanocubes showed only a 1.6-fold enhancement in 4-nitrophenol reduction. This study emphasizes the importance of tuning the size of intermetallic nanocrystals, providing valuable insights for future exploration of their size-dependent properties.

中文翻译：

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探索微调金属间化合物 PdCd 纳米立方体尺寸中与尺寸相关的光学性质变化


由于表面自由能和表面扩散对湿化学生长过程中无序相变的影响相互冲突，因此调整金属间化合物纳米晶体的尺寸具有挑战性。在此，我们通过使用湿化学方法调整 Cd 前驱体浓度，合成了具有 8 至 15 nm 可调尺寸的金属间化合物 PdCd 纳米立方体。该过程具有类似于量子点合成的尺寸调整机制，涉及由前驱体浓度决定的单体浓度的调节。与类似尺寸范围的铂族金属纳米晶体相比，金属间化合物 PdCd 纳米立方体表现出独特的尺寸依赖性光学特性，随着尺寸的增加，光诱导催化增强增加。15 nm 尺寸的纳米立方体表现出最显着的光诱导催化增强，达到 3.3 倍，而 8 nm 尺寸的纳米立方体在 4-硝基苯酚还原方面仅表现出 1.6 倍的增强。本研究强调了调整金属间化合物纳米晶体尺寸的重要性，为未来探索其尺寸依赖性特性提供了有价值的见解。