Influence of Carbon Nanotube Hydrodynamic Radius on Electrical Conductivity in Photoresists

Tuning the electrical properties of biocompatible materials with minimal amounts of nanofiller presents a significant challenge in neuroimplant development. This study investigates the influence of single-walled carbon nanotube (SWCNT) agglomerate size on the electrical conductivity of a bioinspired biopolymer composite. The composites were fabricated via photolithography. We analyzed the effect of ultrasonic homogenization on the size distribution of SWCNT bundles. Our results demonstrate that the degree of nanotube dispersion is critical for determining electrical conductivity. The highest conductivity was achieved with an average bundle size of 95 µm and a defect level of no more than 0.143, as measured by the ID/IG+ band ratio using Raman spectroscopy. We attribute this to the formation of an interconnected percolation network within the biopolymer matrix. These findings demonstrate a viable approach for controlling the conductive properties of bioinspired composites.