From the art desk
Professor Wu explains: "The idea of the cover begins with a Rubik's Cube. I love to play the Rubik's Cube in my spare time, which can not only make the brain flexible, but also exercise the spatial thinking ability. I think the little hexahedron is so changeable and mysterious. There are various permutations and combinations but only one optimum solution.
"This is analogous to our upconversion materials – only when the sensitizer ions and activator ions are arranged at the optimal concentrations do they emit the strongest excitation. We displayed the 17 rare earth elements on our Rubik's Cube, indicating well-designed upconversion materials.
"The ultimate aim of this work is to help solve the urgent energy and environment crisis. Therefore, the background of this cover is our common homeland, the beautiful earth. We hope that with the help of our upconversion photocatalysts the earth will become more beautiful."
Professor Wu’s coworkers, Dr Tian and Dr Yao, helped to design the cover image.
Read the article: Qingyong Tian et al, Nanoscale Horiz., 2019, 4, 10–25, DOI: 10.1039/C8NH00154E
This image appears on the front cover of Nanoscale Horizons, 2019, Issue 1.