Engineering Porous Emitting Framework Nanoparticles with Integrated Sensitizers for Low‐Power Photon Upconversion by Triplet Fusion
Author(s) -
Perego Jacopo,
Pedrini Jacopo,
Bezuidenhout Charl X.,
Sozzani Piero E.,
Meinardi Francesco,
Bracco Silvia,
Comotti Angiolina,
Monguzzi Angelo
Publication year - 2019
Publication title -
advanced materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.707
H-Index - 527
eISSN - 1521-4095
pISSN - 0935-9648
DOI - 10.1002/adma.201903309
Subject(s) - materials science , photon upconversion , nanoparticle , photochemistry , triplet state , quenching (fluorescence) , nanotechnology , optoelectronics , fluorescence , doping , chemistry , organic chemistry , optics , molecule , physics
Abstract The conversion of low‐energy light into photons of higher energy based on sensitized triplet–triplet annihilation ( s TTA) upconversion is emerging as the most promising wavelength‐shifting methodology because it operates efficiently at excitation powers as low as the solar irradiance. However, the production of solid‐state upconverters suited for direct integration in devices is still an ongoing challenge owing to the difficulties concerning the organization of two complementary moieties, the triplet sensitizer, and the annihilator, which must interact efficiently. This problem is solved by fabricating porous fluorescent nanoparticles wherein the emitters are integrated into robust covalent architectures. These emitting porous aromatic framework ( e PAF) nanoparticles allow intimate interaction with the included metallo‐porphyrin as triplet sensitizers. Remarkably, the high concentration of framed chromophores ensures hopping‐mediated triplet diffusion required for TTA, yet the low density of the framework promotes their high optical features without quenching effects, typical of the solid state. A green‐to‐blue photon upconversion yield as high as 15% is achieved: a record performance among annihilators in a condensed phase. Furthermore, the engineered e PAF architecture containing covalently linked sensitizers produces full‐fledge solid‐state bicomponent particles that behave as autonomous nanodevices.