Comparative Study of Surfactants in Graphene Conductive Inks: From Dispersion Mechanisms to Electrical Properties
نویسندگان
1 Department of Printing Science and Technology, Institute for Color Science and Technology, P.O. Box: 16765-654, Tehran, Iran
2 Department of Color Physics, Institute for Color Science and Technology, P.O. Box: 16765-654, Tehran, Iran
3 Department of Printing Science and Technology, Institute for Color Science and Technology, P.O. Box: 16765-654, Tehran, Iran
4 Department of Printing Science and Technology, Institute for Color Science and Technology, P.O. Box: 16765-654, Tehran, Iran
doi
10.30509/pccc.2025.167556.1398چکیده
The development of environmentally friendly, water-based conductive inks with exceptional dispersion stability and electrical conductivity is crucial for advancing next-generation printed electronics. This study systematically investigates the effects of surfactant type (SDBS, SDS, CTAB, and Triton X-100) and concentration on the dispersion stability and conductivity of graphene-based conductive inks. After scrutinizing the effect of surfactant type, the influence of its concentration has been investigated by sweeping the surfactants concentration in the range of 0.1 to 0.75 % (w/w). Moreover, the effects of surfactant concentration and various milling process (Ultrasonication, Jar Milling, and Magnetic Stirring) on conductivity are studied. UV-Vis. spectrophotometry, turbidimetry, particle size analysis, SEM, Confocal Raman analysis and four probe conductivity- meter are used for evaluation of dispersion stability and conductivity. Results revealed that anionic surfactants, particularly SDBS, outperformed cationic and nonionic surfactants due to enhanced electrostatic repulsion and π-π interactions with graphene. It was revealed that the optimal properties are obtainable by SDBS with 0.1 % (w/w), far below its critical micelle concentration which minimized micelle formation and improved conductivity. Magnetic stirring emerged as the most effective dispersion method, minimizing structural defects and achieving the lowest electrical resistivity (24-32 mΩ). The optimized formulation (0.1 % SDBS with magnetic stirring) resulted in a 15 % reduction in electrical resistivity compared to the standard formulation. The findings provide a rational framework for surfactant selection and ink formulation, paving the way for high-performance conductive inks in flexible electronics and other applications.