Highly conductive candle-soot-based polymer composite as a conductive ink for electronic applications

Carbon-based conductive inks, with their low cost, ease of fabrication, and environmental friendliness, have a wide range of applications. In this study, we present the development of a candle-soot-based conductive ink through a simple and cost-effective synthesis process. The composite was formulated by incorporating candle-soot with PVDF-HFP polymer using DMF as a solvent. The study evaluates the performance of different amounts of carbon present in a candle-soot-polymer composite. The conductive ink was also filled in a ballpoint refill, circuits were drawn, and I-V responses were studied. The conductive films were thoroughly characterized using SEM, EDX, TGA, and IV characteristics. XRD and FTIR analyses were performed to assess the properties of the conductive film (CPC4) and candle-soot. Four distinct conductive ink formulations were synthesized by varying the percentage of candle-soot. I-V studies revealed that the electrical resistance of the composite films decreased with increasing candle-soot content. The results demonstrated excellent conductivity, enabling the fabrication of simple and functional conductive circuits on paper using the developed CPC4 ink. Candle-soot, as filler, exhibited promising results comparable to expensive conductive fillers such as graphene and multi-walled carbon nanotubes. The developed conductive ink shows promising performance in flexible electronic devices, offering a cost-effective and environmentally friendly alternative.