Fahes Abeer, Balan Lavinia, Andreazza-Vignolle Caroline, de Melo Claudia, Zanghi Didier, Andreazza Pascal
Université d'Orléans, CNRS, ICMN, UMR 7374 Orléans France
Université d'Orléans, CNRS, CEMHTI, UPR 3079 Orléans France.
Nanoscale Adv. 2025 May 7. doi: 10.1039/d5na00187k.
An innovative approach combining UV-induced polymerization and ultra-high vacuum (UHV) atomic vapor deposition was developed to synthesize and disperse 2-3 nm AgPt bimetallic nanoparticles (BNPs) within a non-porous poly (dipropylene glycol diacrylate) (PDGDA) matrix, surpassing conventional porous polymer strategies. This method offers unprecedented control over the structural properties of BNPs and in general nanoalloys, with the polymer matrix playing a critical role in regulating nanoparticle formation, spatial arrangement, and size uniformity. The PDGDA matrix enhances nanoparticle stability through steric stabilization and controlled diffusion, effectively maintaining small nanoparticle sizes (∼2.4-2.8 nm) and low dispersity ( / = 0.16) during extended high-temperature annealing. Confinement of nanoparticles (NPs) was significantly accelerated by successive thermal annealing to 320 °C, which increased polymer chain mobility and reduced viscosity, enabling rapid diffusion while preserving the structural integrity of the polymer matrix. This process dramatically reduced the embedding time from 12 days at room temperature to near-instantaneous incorporation upon heating. Successful confinement is attributed to key thermodynamic factors that promote interfacial interactions and particle mobility within the polymer network. Experimental results reveal distinctive UV plasmonic properties of the embedded AgPt BNPs with long-term stability. The produced AgPt BNPs exhibit significantly stronger localized surface plasmon resonances (LSPRs) than pure platinum nanoparticles, attributed to synergistic effects between the two metals. Factors contributing to this enhancement include silver's high electrical conductivity and relatively low optical losses, electromagnetic coupling, and localized electric field enhancement, highlighting the potential of these BNPs for advanced plasmonics. This research addresses the growing demand for surface-enhanced Raman scattering (SERS) detection of UV-absorbing biospecies and the development of more efficient broad-spectrum solar cells.
开发了一种将紫外线诱导聚合与超高真空（UHV）原子气相沉积相结合的创新方法，以在无孔聚（二丙二醇二丙烯酸酯）（PDGDA）基质中合成并分散2-3纳米的AgPt双金属纳米颗粒（BNP），超越了传统的多孔聚合物策略。该方法对BNP以及一般的纳米合金的结构特性提供了前所未有的控制，聚合物基质在调节纳米颗粒的形成、空间排列和尺寸均匀性方面起着关键作用。PDGDA基质通过空间稳定化和受控扩散增强了纳米颗粒的稳定性，在长时间高温退火过程中有效地保持了较小的纳米颗粒尺寸（约2.4-2.8纳米）和低分散性（/ = 0.16）。通过连续热退火至320°C，纳米颗粒（NP）的限制显著加速，这增加了聚合物链的流动性并降低了粘度，使得在保持聚合物基质结构完整性同时能够快速扩散。这个过程将嵌入时间从室温下的12天大幅缩短至加热时几乎瞬间掺入。成功的限制归因于促进聚合物网络内界面相互作用和颗粒迁移率的关键热力学因素。实验结果揭示了嵌入的AgPt BNP具有长期稳定性的独特紫外等离子体特性。所制备的AgPt BNP表现出比纯铂纳米颗粒明显更强的局域表面等离子体共振（LSPR），这归因于两种金属之间的协同效应。导致这种增强的因素包括银的高电导率和相对较低的光学损耗、电磁耦合以及局域电场增强，突出了这些BNP在先进等离子体学方面的潜力。这项研究满足了对吸收紫外线的生物物种进行表面增强拉曼散射（SERS）检测以及开发更高效的广谱太阳能电池日益增长的需求。
