A combined system of Raman spectroscopy and STM has been set up, which enables the two techniques to in-situ study electrochemical interfaces simultaneously, An optical fiber head carrying one excitation fiber and fiv...A combined system of Raman spectroscopy and STM has been set up, which enables the two techniques to in-situ study electrochemical interfaces simultaneously, An optical fiber head carrying one excitation fiber and five collection fibers can be adjusted to approach to an advanced originally designed STM unit so that the STM tip above the sample electrode are surrounded by the sir fibers. The strong thermal interface by the laser illumination was avoided with the short acquisition time for SERS measurements by using optical multichannel analyzer. In-situ SERS spectrum of SCN- adsorbed on Ag electrode surface has been simultaneously recorded during STM imaging. The STM imaging taken before, during and after the SERS measurements have drifted from each other within 5%, which shows that the combined system is of satisfied over all stability.展开更多
Two_dimensional arrays of Cu and Au nanowires have been fabricated by template synthesis method, using the anodic aluminum oxidation films as the template. The morphology of the nanowire array was monitored by atomic ...Two_dimensional arrays of Cu and Au nanowires have been fabricated by template synthesis method, using the anodic aluminum oxidation films as the template. The morphology of the nanowire array was monitored by atomic force microscope (AFM) in the dissolution processes of the alumina film. Based on the probe molecule strategy, the spectral feature of SCN - adsorbed at the Cu and Au nanowires with different diameters has been investigated by surface enhanced Raman spectroscopy (SERS). The results reveal that the intensity of the SERS bands depends on the length of the exposed nanowires. The C≡N stretching vibration frequency (ν CN ) of SCN - up_shifted significantly with the increase of the diameter of the nanowires in the range of 15 nm to 50 nm. This interesting phenomenon is briefly discussed.展开更多
The etching resolution of electrochemical fabrication technique is influenced significantly by the diffusion layer of the etchant. It has been shown that a fast etching rate can achieve higher etching resolution due t...The etching resolution of electrochemical fabrication technique is influenced significantly by the diffusion layer of the etchant. It has been shown that a fast etching rate can achieve higher etching resolution due to so-called heterogeneous scavenging effect, while a lower etching rate will result in rather lower etching resolution. For the latter case, the confined etchant layer technique(CELT) has been employed to improve the etching resolution. i. e., a certain redox couple which can consume the etchant homogeneously and rapidly was added to the solution. The homogeneous scavenging effect confined the etchant within a narrow layer around the electrode surface and much improved etching resolution was achieved. Using the CELT and a needle-shaped microelectrode, an etching spot of several micro-meters was obtained at silicon wafer surface.展开更多
基金supported by the National Natu-ral Science Foundation of China(No.22002129,No.21972119,No.21991151,No.22202162,No.22102137,No.22072123)the China Post-doctoral Science Foundation(No.2019TQ0177,No.2022T150548,No.2022M722648).
文摘A combined system of Raman spectroscopy and STM has been set up, which enables the two techniques to in-situ study electrochemical interfaces simultaneously, An optical fiber head carrying one excitation fiber and five collection fibers can be adjusted to approach to an advanced originally designed STM unit so that the STM tip above the sample electrode are surrounded by the sir fibers. The strong thermal interface by the laser illumination was avoided with the short acquisition time for SERS measurements by using optical multichannel analyzer. In-situ SERS spectrum of SCN- adsorbed on Ag electrode surface has been simultaneously recorded during STM imaging. The STM imaging taken before, during and after the SERS measurements have drifted from each other within 5%, which shows that the combined system is of satisfied over all stability.
文摘Two_dimensional arrays of Cu and Au nanowires have been fabricated by template synthesis method, using the anodic aluminum oxidation films as the template. The morphology of the nanowire array was monitored by atomic force microscope (AFM) in the dissolution processes of the alumina film. Based on the probe molecule strategy, the spectral feature of SCN - adsorbed at the Cu and Au nanowires with different diameters has been investigated by surface enhanced Raman spectroscopy (SERS). The results reveal that the intensity of the SERS bands depends on the length of the exposed nanowires. The C≡N stretching vibration frequency (ν CN ) of SCN - up_shifted significantly with the increase of the diameter of the nanowires in the range of 15 nm to 50 nm. This interesting phenomenon is briefly discussed.
文摘The etching resolution of electrochemical fabrication technique is influenced significantly by the diffusion layer of the etchant. It has been shown that a fast etching rate can achieve higher etching resolution due to so-called heterogeneous scavenging effect, while a lower etching rate will result in rather lower etching resolution. For the latter case, the confined etchant layer technique(CELT) has been employed to improve the etching resolution. i. e., a certain redox couple which can consume the etchant homogeneously and rapidly was added to the solution. The homogeneous scavenging effect confined the etchant within a narrow layer around the electrode surface and much improved etching resolution was achieved. Using the CELT and a needle-shaped microelectrode, an etching spot of several micro-meters was obtained at silicon wafer surface.
