Complex Copper Nanostructures for Fluid Sensing-a Comparative Study of the Performance of Helical and Columnar Thin Films

This communication is pivoted to the sensing of fluids by the use of nanoengineered thin films comprised of copper nano-helixes as well as copper nano-rods, in order to study the comparison of the performance of thin films having different morphological features. For this purpose, human blood samples having different concentrations of haemoglobin are taken into account as measurands. The sensing configuration exploits the use of nanostructured metallic thin films grown over glass substrate with the void regions filled up with measurands, and the features of absorption spectra are monitored. Two different wavelengths are used along with two different values of helix pitch angle as well as slanting angle of nano-rods, and the focus is put on the effect due to these parameters on the sensing characteristics. It is observed that in the case of nano-helix structured films, pitch angle affects spectral characteristics obtained due to the generation of plasmonic waves at the interface of two partnering mediums. Upon comparing the obtained results with those corresponding to thin films comprised of slanted copper nano-rods (having different angles of inclination), it has been found that the nano-helix embedded films provide better appreciable results than those exhibited by the columnar thin films, thereby making the former kind of nanostructured mediums more useful in sensing-related applications.