Synthesis of Carbon-Based Xerogels Inspired by Japanese-Solid-Calligraphy Ink as a Teaching Tool for Exploring Carbon Allotropes

Carbon allotropes─including graphite, graphene, diamond, fullerene, and carbon nanotubes─play vital roles across both scientific and industrial fields. Understanding their unique physical properties is fundamental for education and research alike. This study introduces a novel educational approach that utilizes carbon-based xerogels inspired by traditional Japanese solid-calligraphy ink to support student learning. These xerogels, created by combining various carbon allotropes with animal-derived glue, enable students to observe and compare key characteristics such as visual appearance, gloss, surface resistivity, and microscopic structure. The materials are safe, durable, and can be easily redispersed in water, allowing for creative applications in calligraphy and Suiboku-ga (traditional Japanese ink painting). This hands-on, visually engaging activity provides an accessible and memorable introduction to carbon allotropes using simple, familiar materials. Students who participated in this program evaluated the activity positively. They reported that, through the synthesis and characterization of carbon xerogels, they were able to deepen their understanding of carbon allotropes and analytical techniques (e.g., SEM, resistivity measurements) in an enjoyable and engaging way. Moreover, from the perspective of STEAM education, these xerogel-based teaching materials are particularly compelling, as they integrate scientific exploration with Japanese cultural traditions and artistic practices through ink making.