Department of Chemistry, Rice University, Houston, TX 77005, USA.
Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005, USA.
Science. 2018 Oct 5;362(6410):69-72. doi: 10.1126/science.aat6967.
Photocatalysis based on optically active, "plasmonic" metal nanoparticles has emerged as a promising approach to facilitate light-driven chemical conversions under far milder conditions than thermal catalysis. However, an understanding of the relation between thermal and electronic excitations has been lacking. We report the substantial light-induced reduction of the thermal activation barrier for ammonia decomposition on a plasmonic photocatalyst. We introduce the concept of a light-dependent activation barrier to account for the effect of light illumination on electronic and thermal excitations in a single unified picture. This framework provides insight into the specific role of hot carriers in plasmon-mediated photochemistry, which is critically important for designing energy-efficient plasmonic photocatalysts.
基于光学活性的“等离子体”金属纳米粒子的光催化作用已经成为一种很有前途的方法，可以在比热催化温和得多的条件下促进光驱动的化学反应。然而，对于热激发和电子激发之间的关系还缺乏了解。我们报告了在等离子体光催化剂上，氨分解的热激活势垒在光诱导下显著降低。我们引入了一个依赖于光的激活势垒的概念，以在一个单一的统一图像中解释光照射对电子和热激发的影响。这个框架为理解在等离子体介导的光化学中热载流子的具体作用提供了思路，这对于设计节能的等离子体光催化剂至关重要。
