Zhuo Xiaolu, Mychinko Mikhail, Heyvaert Wouter, Larios David, Obelleiro-Liz Manuel, Taboada José M, Bals Sara, Liz-Marzán Luis M
CIC biomaGUNE, Basque Research and Technology Alliance (BRTA), Paseo de Miramón 182, 20014 Donostia-San, Sebastián, Spain.
Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Paseo de Miramón 182, 20014 Donostia-San, Sebastián, Spain.
ACS Nano. 2022 Nov 22;16(11):19281-19292. doi: 10.1021/acsnano.2c08668. Epub 2022 Oct 26.
Chiral plasmonics is a rapidly developing field where breakthroughs and unsolved problems coexist. We have recently reported binary surfactant-assisted seeded growth of chiral gold nanorods (Au NRs) with high chiroptical activity. Such a seeded-growth process involves the use of a chiral cosurfactant that induces micellar helicity, in turn driving the transition from achiral to chiral Au NRs, from both the morphological and the optical points of view. We report herein a detailed study on both transitions, which reveals intermediate states that were hidden so far. The correlation between structure and optical response is carefully analyzed, including the (linear and CD) spectral evolution over time, electron tomography, the impact of NR dimensions on their optical response, the variation of the absorption-to-scattering ratio during the evolution from achiral to chiral Au NRs, and the near-field enhancement related to chiral plasmon modes. Our findings provide further understanding of the growth process of chiral Au NRs and the associated optical changes, which will facilitate further study and applications of chiral nanomaterials.
手性等离子体激元学是一个快速发展的领域，其中突破与未解决的问题并存。我们最近报道了二元表面活性剂辅助的具有高旋光活性的手性金纳米棒（Au NRs）的种子生长。这种种子生长过程涉及使用一种手性共表面活性剂，它能诱导胶束螺旋度，进而从形态学和光学角度驱动从非手性Au NRs到手性Au NRs的转变。我们在此报告对这两种转变的详细研究，揭示了迄今为止隐藏的中间状态。仔细分析了结构与光学响应之间的相关性，包括（线性和圆二色性）光谱随时间的演变、电子断层扫描、纳米棒尺寸对其光学响应的影响、从非手性Au NRs到手性Au NRs演变过程中吸收与散射比的变化，以及与手性等离子体激元模式相关的近场增强。我们的发现为手性Au NRs的生长过程及相关光学变化提供了进一步的理解，这将有助于手性纳米材料的进一步研究和应用。
