Gas bubble evolution is an important phenomenon in many electrochemical processes and it is highly sensitive to the surface properties. Here we visualize the gas bubble dynamics on the surface of different graphene substrates during hydrogen evolution reaction (HER) using atomic force microscopy combined with scanning electrochemical microscopy. The low overpotential and low surface hydrophobicity of few-layer graphene formed on C-phase SiC causes the uniform distribution of hydrogen nanobubbles, which easily depart from the surface during the reaction. Conversely, the high overpotential and more hydrophobic surface of HOPG induces hydrogen bubbles to linger on the surface for an extended duration, leading to its accumulation and the subsequent formation of microbubbles. This in-situ nanoscale electrochemical mapping of hydrogen bubble dynamics provides new insight into electrocatalytic HER that occurs on non-metal electrodes.

中文翻译：

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AFM-SECM 原位观察石墨烯表面氢纳米气泡的形成


气泡演化是许多电化学过程中的重要现象，并且对表面性质高度敏感。在这里，我们使用原子力显微镜与扫描电化学显微镜相结合，对析氢反应（HER）过程中不同石墨烯基材表面上的气泡动力学进行可视化。 C相SiC上形成的少层石墨烯的低过电势和低表面疏水性导致氢纳米气泡分布均匀，在反应过程中很容易脱离表面。相反，HOPG 的高过电势和疏水性表面会导致氢气泡在表面停留较长时间，导致其积累并随后形成微气泡。这种氢气泡动力学的原位纳米级电化学图谱为非金属电极上发生的电催化 HER 提供了新的见解。