Improved Photon Absorption in Dye-Functionalized Silicon Nanocrystals Synthesized via Microwaveassisted Hydrosilylation†

Beri, Deski and Jakoby, Marius and Howard, Ian A. and Busko, Dmitry and Richards, Bryce S. and Turshatov, Andrey (2020) Improved Photon Absorption in Dye-Functionalized Silicon Nanocrystals Synthesized via Microwaveassisted Hydrosilylation†. Dalton Trans. pp. 2290-2299.

Preview

Text DESKI_BERI_Improved_photon_absorption_dye_functionalized.pdf Download (1MB) | Preview

Abstract

Herein, we report a method to produce luminescent silicon nanocrystals (SiNc) that strongly absorb ultraviolet–visible light (300–550 nm) and emit in the near-infrared range (700–1000 nm) with a high photo- luminescence quantum yield (PLQY). Using microwave-assisted hydrosilylation and employing reactive chromophores – such as ethenyl perylene, ethynyl perylene and ethylene-m-phenyl BODIPY – we are able to achieve a 10- and 3-fold enhancement of the absorption in the blue and green spectral range, respectively. The investigated dyes function both as passivating agents and highly efficient antenna, which absorb visible light and transfer the energy to SiNc with an efficiency of >95%. This enhanced absorption leads to a significant photoluminescence enhancement, up to ∼270% and ∼140% under excitation with blue and green light, respectively. Despite the gain in absolute brightness of the emission, we demonstrate that back energy transfer from the SiNc to the dyes leads to a decrease in the PLQY for dyemodified SiNc, as compared to unmodified SiNc. The synthesis of the SiNc-dye conjugates opens up new possibilities for applications of this abundant and non-toxic material in the field of solar energy harvesting, optical sensing and bioimaging via achieving strong NIR PL excited with visible light.

Actions (login required)

View Item