Sequential energy transfer is ubiquitous in natural light harvesting systems to make full use of solar energy. Although various artificial systems have been developed with the biomimetic sequential energy transfer character, most of them exhibit the overall energy transfer efficiency lower than 70% due to the disordered organization of donor/acceptor chromophores. Herein a sequential energy transfer system is constructed via supramolecular copolymerization of σ-platinated (hetero)acenes, by taking inspiration from the natural light harvesting of green photosynthetic bacteria. The absorption and emission transitions of the three designed σ-platinated (hetero)acenes range from visible to NIR region through structural variation. Structural similarity of these monomers faciliates supramolecular copolymerization in apolar media via the nucleation-elongation mechanism. The resulting supramolecular copolymers display long diffusion length of excitation energy (> 200 donor units) and high exciton migration rates (~1014 L mol−1 s−1), leading to an overall sequential energy transfer efficiency of 87.4% for the ternary copolymers. The superior properties originate from the dense packing of σ-platinated (hetero)acene monomers in supramolecular copolymers, mimicking the aggregation mode of bacteriochlorophyll pigments in green photosynthetic bacteria. Overall, directional supramolecular copolymerization of donor/acceptor chromophores with high energy transfer efficiency would provide new avenues toward artificial photosynthesis applications.

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Cesium halide lead (CsPbX 3 ) perovskite nanocrystals (NCs) have been extensively studied in recent years for their unique capability of postsynthesis anion exchange, providing facile tunability of band gaps and optical properties. In this work, we demonstrate for the first time a simple approach to the tunable anion exchange of CsPbX 3 perovskite NCs via radiation chemistry of inert halohydrocarbons. The anion exchange extents are monitored by shifting of fluorescence emission peaks and ultraviolet−visible absorbance edges and are precisely controlled by tuning the absorbed doses and the adjustable addition of halohydrocarbons. At the same absorbed doses, the anion exchange extents by halohydrocarbons are dependent on the linear attenuation coefficients of halohydrocarbons. Radiation-induced anion exchange can passivate defects in CsPbX 3 NCs, resulting in the fluorescence enhancement. The morphology of perovskite NCs almost remains intact after radiation-induced anion exchange.

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