Application of spectromicroscopy tools to explore local origins of sensor activity in quasi-1D oxide nanostructures

We have tested a range of imaging and spectroscopic techniques to address their ability to locally explore the interplay between surface reactivity and transport properties of the metal oxide nanostructure wired as a chemiresistor and chemi-FET. In particular, we used scanning surface potential microscopy (SSPM) to monitor the spatial and temporal particularities of the dc potential distributions in an operating device. We also successfully implemented synchrotron radiation-based photoelectron emission microscopy (PEEM) to explore submicron lateral compositional and electronic (work function) inhomogeneity on the surface of an individual nanowire sensor. These results open new avenues to visualize and spectroscopically address the chemical phenomena on an individual quasi-1D nanostructure both in real time and at nano- and mesoscopic level.