Driving energetically unfavorable dehydrogenation dynamics with plasmonics
Driving energetically unfavorable dehydrogenation dynamics with plasmonics
复制标题
DOI：
10.1126/science.abd2847
复制
发表时间：
2021-01-15
期刊：
影响因子：
56.9
通讯作者：
Dionne, Jennifer A.
中科院分区：
文献类型：
--
作者：
Sytwu, Katherine;Vadai, Michal;Dionne, Jennifer A.
纳米颗粒表面结构和几何形状通常决定了化学转化发生的位置，在具有较低活化能的位点具有较高的化学活性。在这里，我们展示了等离子体激元的光激发如何使空间修改的相变，激活否则能量不利的网站。我们设计了一个十字棒Au-PdHx天线反应器系统，该系统将电磁增强定位在远离固有反应性PdHx纳米棒尖端的位置。使用光耦合原位环境透射电子显微镜，我们跟踪不同的光照明强度，波长和氢气压力的个别天线反应器对脱氢。我们的原位实验表明，等离子体激元使新的催化位点，包括在纳米棒面脱氢。分子动力学模拟证实，这些新的成核位点在平衡状态下是能量上不利的，并且只能通过定制的等离子体激元激发来访问。
Nanoparticle surface structure and geometry generally dictate where chemical transformations occur, with higher chemical activity at sites with lower activation energies. Here, we show how optical excitation of plasmons enables spatially modified phase transformations, activating otherwise energetically unfavorable sites. We have designed a crossed-bar Au-PdHx antenna-reactor system that localizes electromagnetic enhancement away from the innately reactive PdHx nanorod tips. Using optically coupled in situ environmental transmission electron microscopy, we track the dehydrogenation of individual antenna-reactor pairs with varying optical illumination intensity, wavelength, and hydrogen pressure. Our in situ experiments show that plasmons enable new catalytic sites, including dehydrogenation at the nanorod faces. Molecular dynamics simulations confirm that these new nucleation sites are energetically unfavorable in equilibrium and only accessible through tailored plasmonic excitation.