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Using ligand exchange on FAPbI3 perovskite nanocrystals (PNCs) surface with chiral tridentate L-cysteine (Lcys) ligand, we successfully prepared chiral FAPbI3 PNCs that show circularly polarized luminescence (CPL) (dissymmetry factor; glum = 2.1 × 10−3) in the near-infrared (NIR) region from 700 to 850 nm and a photoluminescence quantum yield (PLQY) of 81%. The chiral characteristics of FAPbI3 PNCs are ascribed to induction by chiral L/D-cys, and the high PLQY is attributed to the passivation of the PNCs defects with L-cys. Also, effective passivation of defects on the surface of FAPbI3 PNCs by L-cys results in excellent stability toward atmospheric water and oxygen. The conductivity of the L-cys treated FAPbI3 NC films is improved, which is attributed to the partial substitution of L-cys for the insulating long oleyl ligand. The CPL of the L-cys ligand treated FAPbI3 PNCs film retains a glum of −2.7 × 10−4. This study demonstrates a facile yet effective approach to generating chiral PNCs with CPL for NIR photonics applications.
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Decoupling Activity and Specificity in Coronazymes
Abstract Specificity and activity are often at odds for natural enzymes. In this work, specificity and activity in coronazymes made of an Au nanoparticle (AuNP) and coated with DNA aptamer for glucose substrates are decoupled. By single‐molecule fluorescent MT‐HILO (magnetic tweezers coupled with highly inclined and laminated optical sheet) microscopy, it is found that this coronazyme has ≈30 times higher activity on thed‐glucose compared to bare AuNP nanozymes. Significantly, the new coronazyme demonstrates long‐range modulations by circularly polarized light (CPL) according to the matching chirality between the CPL and DNA corona, which follows the rule of chiral induced spin selectivity (CISS). Although the aptamer in the coronazyme is evolved againstd‐glucose, surprisingly, this coronazyme catalyzesl‐glucose better thand‐glucose, likely due to the faster rates for the aptamer to interact with thel‐ overd‐glucose. These results demonstrate, for the first time, an artificial enzyme with its catalytic activity controlled by short‐range intermolecular forces, whereas its chiral specificity is modulated by long‐range CPLs. This decoupled arrangement is pivotal to forge premier catalysts with activity and specificity superior to natural enzymes by separately optimizing these two properties.
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- Award ID(s):
- 2247709
- PAR ID:
- 10576955
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 21
- Issue:
- 14
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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