Résumé
We demonstrate an improvement of the emission quantum yield and the luminance figures of merit of metal-free bridged silsesquioxanes--by a factor of 2, 0.43 ± 0.04, and by two orders of magnitude, (1.4 ± 0.1) x 104 cd m-2, respectively--by changing the regioisomer of the silylated precursor. The organic-inorganic hybrids are easily excited by commercial blue InGaN-based light emitting diodes (LEDs) displaying an intriguing potential to applications in green photonics as metal-free phosphors for solid state lighting.