金屬奈米晶體，例如Ag和Pt奈米晶體，由於其具有高活性而被廣泛地用作各種化學反應之觸媒。且此類材料用於觸媒應用上的活性可以通過將多成分材料形成之奈米晶體(協同效應)或增加此類晶體材料形態的非均質性(高表面積體積比)來進一步增強。在這裡，我們通過“晶種介導”合成方法將晶種固定於疏水層之表面上來製備具有高度非均質形態(蘑菇狀/花狀/半框架狀)的Pt-Ag奈米晶體，此固定於疏水層表面之奈米晶體可以用於抑制奈米晶體作為觸媒應用時所產生聚集問題。當這些Pt-Ag奈米晶體用作4-硝基苯酚還原觸媒時，這些奈米晶體的催化性能在很大程度上取決於奈米晶體的組成和形態。與蘑菇狀的Pt-Ag奈米晶體相比，花狀和半框架狀的Pt-Ag奈米晶體表現出更佳的催化活性，這歸因於它們的花狀奈米晶體的形態效應(高表面積體積比)和半框架狀奈米晶體的組成效應(協同效應)。與文獻中報告的其他Pt/Ag/Pt-Ag的奈米晶體作為4-硝基苯酚(4-NP)還原觸媒相比，這些位於疏水層表面之高度非均質性的Pt-Ag奈米晶體顯示出顯著的催化性能增強效果，這可以歸因於它們的組合和形態效應以及有效的抑制奈米晶體之聚集。由於Ag奈米晶體在可見光下顯現出優越電漿子響應，使這些Pt-Ag奈米晶體還可以被用作於可見光照射下的光觸媒，來進一步提升其催化性能。

The study explores Pt-Ag nanocrystals with varied morphologies (mushroom-like, flower-like, half-cage-like) synthesized via a seed-mediated method in a hydrophobic layer. These nanocrystals are designed to address aggregation issues, enhancing their efficacy as catalysts. In catalyzing 4-nitrophenol reduction, their performance hinges on morphology and composition. Flower-like and half-cage-like morphologies exhibit superior catalytic activity due to high surface area and synergistic effects, respectively. Compared to existing Pt/Ag nanocrystals, these heterogeneous structures demonstrate significant enhancements, attributed to morphology and composite effects. Moreover, their plasmonic response under visible light enhances their utility as photocatalysts.

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