Fiber optical laser spot microscope: A new concept for photoelectrochemical characterization of semiconductor electrodes

摘要

A fiber optical laser spot microscope, which allows the simultaneous measurements of photocurrent and reflected light intensity or the measurement of laser spot photocurrent under the illumination of other light sources, has been developed to study semiconductor/electrolyte interfaces. The capability of this microscope was demonstrated on as-cleaved and Pt-treated p-InSe. The Pt treatment increased the photocurrent and improved the lateral resolution due to the increase of surface reaction rate. The higher photocurrent was observed at the spot where the reflectivity was higher. This behavior is considered to be due to an uneven distribution of platinum. The laser spot photocurrent image under the illumination of other light sources provided useful information to clarify whether the rate was controlled by surface or bulk properties of InSe.