International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China.
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China.
Science. 2022 Jul 15;377(6603):315-319. doi: 10.1126/science.abo0823. Epub 2022 Jul 14.
The nature of hydrated proton on solid surfaces is of vital importance in electrochemistry, proton channels, and hydrogen fuel cells but remains unclear because of the lack of atomic-scale characterization. We directly visualized Eigen- and Zundel-type hydrated protons within the hydrogen bonding water network on Au(111) and Pt(111) surfaces, using cryogenic qPlus-based atomic force microscopy under ultrahigh vacuum. We found that the Eigen cations self-assembled into monolayer structures with local order, and the Zundel cations formed long-range ordered structures stabilized by nuclear quantum effects. Two Eigen cations could combine into one Zundel cation accompanied with a simultaneous proton transfer to the surface. Moreover, we revealed that the Zundel configuration was preferred over the Eigen on Pt(111), and such a preference was absent on Au(111).
在电化学、质子通道和氢燃料电池中，固 体表面上水合质子的性质至关重要，但由于缺乏原子尺度的表征，其性质仍不清楚。我们使用 cryogenic qPlus 基于原子力显微镜在超高真空下直接观察到 Au(111)和 Pt(111)表面氢键网络中的 Eigen- 和 Zundel 型水合质子。我们发现，Eigen 阳离子自组装成具有局部有序的单层结构，而 Zundel 阳离子则形成由核量子效应稳定的长程有序结构。两个 Eigen 阳离子可以结合成一个 Zundel 阳离子，同时质子转移到表面。此外，我们揭示了在 Pt(111)上，Zundel 结构优先于 Eigen，而在 Au(111)上则不存在这种偏好。
