Watching Plasmon-Induced Nanoparticle Ostwald Ripening
Watching Plasmon-Induced Nanoparticle Ostwald Ripening
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DOI：
10.1021/acs.jpcc.3c04035
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发表时间：
2023-08-09
影响因子：
3.7
通讯作者：
Jain，Prashant K.
中科院分区：
文献类型：
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作者：
Alcorn，Francis M.;Chattoraj，Maya;Jain，Prashant K.
光吸收等离子体纳米结构被用于各种应用，包括荧光和传感。由于结构与功能和性能密切相关，因此必须了解这些材料的结构在光激发下如何演变，以及这些结构转变的类型和原子性质。利用具有激光激发功能的透射电子显微镜，我们对等离子体激发下的Au-Cu合金纳米颗粒的结构进行了监测。发现等离子体激元激发诱导纳米颗粒的奥斯特瓦尔德熟化。这个过程发生在一个开关一样的方式不同于电子束诱导的聚结，我们也观察到。这种结构转变不是由加热引起的，并且是由等离子体激元激发的载流子引起的非热结构转变的示例。这些结果告诉我们等离子体纳米结构的潜在转变，可能发生在等离子体激元电催化或等离子体激元辅助电催化的操作条件下，其中支撑在衬底上的等离子体纳米颗粒的高面密度经受连续光激发。
Light-absorbing plasmonic nanostructures are used in a variety of applications, including photocatalysis and sensing. Because structure is intricately linked to function and performance, it is essential to understand how the structures of these materials might evolve under light excitation and what are the types and atomic natures of these structural transformations. Using a transmission electron microscope equipped with the capability of laser excitation of the specimen, we monitored the structures of Au–Cu alloy nanoparticles under plasmonic excitation. Plasmonic excitation was found to induce Ostwald ripening of nanoparticles. This process occurs in a switch-like manner distinct from electron-beam-induced coalescence that we also observe. This structural transformation is not induced by heating and is an example of a nonthermal structural transformation induced by plasmonically excited carriers. These results inform us about potential transformations of plasmonic nanostructures that can occur under operating conditions of plasmonic photocatalysis or plasmon-assisted electrocatalysis, where a high areal density of plasmonic nanoparticles supported on a substrate is subjected to continuous light excitation.