Cascade exciton-pumping engines with manipulated speed and efficiency in light-harvesting porous π-network films

Abstract

Light-harvesting antennae are the machinery for exciton pumping in natural photosynthesis, whereas cascade energy transfer through chlorophyll is key to long-distance, efficient energy transduction. Numerous artificial antennae have been developed. However, they are limited in their cascade energy-transfer abilities because of a lack of control over complex chromophore aggregation processes, which has impeded their advancement. Here we report a viable approach for addressing this issue by using a light-harvesting porous polymer film in which a three-dimensional π-network serves as the antenna and micropores segregate multiple dyes to prevent aggregation. Cascade energy-transfer engines are integrated into the films; the rate and efficiency of the energy-funneling engines are precisely manipulated by tailoring the dye components and contents. The nanofilms allow accurate and versatile luminescence engineering, resulting in the production of thirty emission hues, including blue, green, red and white. This advance may open new pathways for realising photosynthesis and photoenergy conversion.

Design of Highly Photofunctional Porous Polymer Films with Controlled Thickness and Prominent Microporosity

“…The porous films prepared by electropolymerization that have been reported to date are not based on AIE units, and the most emissive had a quantum yield of only 19 %. [6c] The integration of AIE units dramatically enhanced the photoluminescence capability, with an increase in the quantum yield to 40 %. Notably, the luminescence activity of the porous polyTPECz films is the highest reported for AIE-based porous materials to date; these materials typically have a quantum yield of only a few percent (see Table S1).…”

Luminescent Porous Polymers Based on Aggregation‐Induced Mechanism: Design, Synthesis and Functions

“…Porous organic polymers (POPs) are a unique class of amorphous porous polymers that combine covalent π‐networks with inherent porosity. POPs are a class of emerging multifunctional materials and show outstanding properties and functions in various applications, such as gas storage, light emitting, catalysis, energy transfer and energy storage . They are robust in stability as a result of strong covalent bond‐linked network structure and can be synthesized using a variety of different π‐units.…”

“…Electropolymerization is a powerful method to prepare polymer films on electrodes, whereas the precursors are oxidized electrochemically and the coupling reaction between the precursors occurs at the electrode surface with deposition of the polymer film onto the electrode . As a proof of concept, a triphenylbenzene (TPB, 36 ) based monomer with three electrochemical active carbazole units on the periphery ( Figure a) has been utilized; the synthesis of crosslinked POP films becomes possible based on electropolymerization at a solution‐electrode interface for the simultaneous polymerization and deposition of porous polymer films on electrodes .…”

Electrochemically Generated Thin Films of Microporous Polymer Networks: Synthesis, Properties, and Applications

“…Microporous polymer films ( P4 ) based on monomer 4 have been used as light‐harvesting antennae for exciton pumping by Jiang and co‐workers . The thin films of P4 were synthesized on ITO by potentiodynamic electrochemical polymerization in dichloromethane solution.…”

“…h) Luminescence engineering of 30 dye‐infiltrated P4 films with the corresponding Commission Internationale de L'eclairage (CIE) coordinates. Adapted with permission . 2015, Nature Publishing Group.…”