Solid–liquid–gas reactions are ubiquitous and are encountered in both nature and industrial processes^1,2,3,4. A comprehensive description of gas transport in liquid and following reactions at the solid–liquid–gas interface, which is substantial in regard to achieving enhanced triple-phase reactions, remains unavailable. Here, we report a real-time observation of the accelerated etching of gold nanorods with oxygen nanobubbles in aqueous hydrobromic acid using liquid-cell transmission electron microscopy. Our observations reveal that when an oxygen nanobubble is close to a nanorod below the critical distance (~1 nm), the local etching rate is significantly enhanced by over one order of magnitude. Molecular dynamics simulation results show that the strong attractive van der Waals interaction between the gold nanorod and oxygen molecules facilitates the transport of oxygen through the thin liquid layer to the gold surface and thus plays a crucial role in increasing the etching rate. This result sheds light on the rational design of solid–liquid–gas reactions for enhanced activities.

固-液-气反应无处不在，在自然界和工业过程中都会遇到^1,2,3,4. 对液体中的气体传输以及固-液-气界面处的后续反应的全面描述，这对于实现增强的三相反应非常重要，但仍然无法获得。在这里，我们报告了使用液体细胞透射电子显微镜实时观察在氢溴酸水溶液中用氧纳米气泡加速金纳米棒的蚀刻。我们的观察表明，当氧纳米气泡接近临界距离（~1 nm）以下的纳米棒时，局部蚀刻速率显着提高了一个数量级以上。分子动力学模拟结果表明，金纳米棒与氧分子之间的强吸引力范德华相互作用促进了氧通过薄液层传输到金表面，从而对提高蚀刻速率起着至关重要的作用。这一结果为合理设计固-液-气反应以增强活性提供了启示。