Despite advances in LED technology, lighting continues to consume a significant amount of energy, especially in urban and transport settings, and remain a challenge for urban planners as modern societies move towards smart cities and zero energy buildings. Through the rational design of long afterglow pigments, we are developing materials that consume no energy from the power grid. To date, the commercially available ceramic phosphors with extremely long afterglow and sufficient intensity suitable for passive illumination are limited. We adopt an interdisciplinary approach in the design of optical materials by a combination of synthesis and atomic resolution spectroscopy and construction materials exploiting the long afterglow properties. While advancing the field of optical materials engineering, this project will also have substantial impact on urban lighting and the future design of public spaces and transport in smart cities.

• G. Inan Akmehmet, S. Šturm, L. Bocher, M. Kociak, B. Ambrožič, C.W. Ow-Yang, “Structure and Luminescence in Long Persistence Eu and Dy Co-doped Strontium Aluminate Phosphors: the Boron Effect,” J. Am. Ceram. Soc. 99 [6], 2175–2180 (2016). DOI:10.1111/jace.14188.