Maya blue, an ancient guest-host pigment: Synthesis and models

摘要

The blue of the ancient Maya civilization, Maya blue (MB), can be an excellent example for the introduction of composite materials at high school or at first-year college levels. In addition to the synthesis of MB, made according to an old recipe, a simple model of beads and LEDs has been developed mimicking this organic-inorganic hybrid (a mixture of the organic dye indigo with a clay: palygorskite). This allows teaching-learning activities where the instructor can (i) explore the rich history of MB (including that of indigo); (ii) perform the synthesis of MB in the lab; (iii) reveal the remarkable stability of MB; and finally (iv) lead the student to understand the interactions between indigo individual molecules and the clay host in MB using an imaginative and simple model.