Chemometric Evaluation of Ultraviolet-Visible (UV-Vis) Spectra for Characterization of Silver Nanowire Diameter and Yield.

The main tool used for routine screening of silver nanowire diameter and wire-to-particle yield is ultraviolet-visible (UV-Vis) spectroscopy. The normalized absorbance near 500 nm is generally taken to correlate with wire yield (lower absorbance means fewer particles and higher wire yield). The location of the UV-Vis peak near 375 nm is generally believed to correlate with wire diameter. These qualitative assessments are of unknown uncertainty. Improved microscopy-based analysis of wire diameter distribution and wire yield had recently been developed and were used to characterize synthesis products in parallel with UV-Vis data collection. Here we present results of leveraging this quantitative wire yield and diameter distribution data to quantitatively calibrate the UV-Vis methods for characterizing wire diameter and yield. Chemometric analysis was also applied to this UV-Vis data set and resulted in statistically significant models that can predict average wire diameter and wire/particle yield slightly better than the univariate method.