Surface-enhanced Raman spectroscopy (SERS) is a vibrational spectroscopy technique with sensitivity down to the single molecule level that provides fine molecular fingerprints, allowing for direct identification of target analytes.

Recently, attention on pyridine adsorption and reaction at the electrode/electrolyte interface has been revitalized in the context of pyridine-mediated reactions such as CO2 reduction. Taking Pt as an example, although numerous efforts have been made, disagreements are still unresolved regarding the potential-dependent adsorption of pyridine on the Pt electrode, which further prevents an explicit understanding of the pyridine-mediated electrochemical process at a molecular level. Here, we employed an operando electrochemical surface-enhanced Raman spectroscopy method, in combination with the density functional theory calculation and isotopic labeling of the molecule, to thoroughly study how pyridine interacts with the Pt electrode/electrolyte interface. For the first time, it is corroborated that pyridine is adsorbed on the Pt electrode in both pyridine molecule (Py) and α-pyridyl radical (α-Pyl) states. On the basis of a systematic investigation of the potential-dependent vibrational spectra, we further explored how the coverage, configuration, and binding strength of both Py and α-Pyl adsorbates on the Pt electrode are tuned by electrode polarization and accordingly established a structural model at the electrochemical interface. Our work not only ends the long-time disputes on how pyridine interacts with the Pt electrode but also provides crucial information for the mechanistic research of pyridine-mediated reaction process.

Piezoelectric nanomaterials open new avenues in driving green catalysis processes (e.g., H2 evolution from water) through harvesting mechanical energy, but their catalytic efficiency is still limited. The predicted enormous piezoelectricity for 2D SnSe, together with its high charge mobility and excellent flexibility, renders it an ideal candidate for stimulating piezocatalysis redox reactions. In this work, few‐layer piezoelectric SnSe nanosheets (NSs) are utilized for mechanically induced H2 evolution from water. The finite elemental method simulation demonstrates an unprecedent maximal piezoelectric potential of 44.1 V for a single SnSe NS under a pressure of 100 MPa. A record‐breaking piezocurrent density of 0.3 mA cm−2 is obtained for SnSe NSs‐based electrode under ultrasonic excitation (100 W, 45 kHz), which is about three orders of magnitude greater than that of reported piezocatalysts. Moreover, an exceptional H2 production rate of 948.4 µmol g−1 h−1 is achieved over the SnSe NSs without any cocatalyst, far exceeding most of the reported piezocatalysts and competitive with the current photocatalysis technology. The findings not only enrich the potential piezocatalysis materials, but also provide useful guidance toward high‐efficiency mechanically driven chemical reactions such as H2 evolution from water.