Plasmon-enhanced chiral absorption through electric dipole-electric quadrupole interaction

Enantioselective interactions of chiral molecules include distinct absorptions to opposite-handed circularly polarized light, known as chiral absorption. Traditionally, chiral absorption has been primarily attributed to electric dipole and magnetic dipole interaction with molecular chirality. However, this approach falls short for large molecules that support high-order multipolar components, such as electric quadrupole moment. Here, we introduce a theoretical model to study the chiral absorption of large molecules in the presence of plasmonic nanostructures. This model considers both electric dipole-magnetic dipole interaction and electric dipole-electric quadrupole interaction enhanced by a resonant structure. We numerically study such interactions of the chiral molecular solution in the vicinity of a nonchiral plasmonic nano-resonator. Our results show the distinct spectral information of the chiral media on- and off-resonance of the resonator

Cellulose Fibers Constructed Convenient Recyclable 3D Graphene-Formicary-like δ‑Bi₂O₃ Aerogels for the Selective Capture of Iodide

Radioiodine is highly radioactive and acutely toxic, which can be a serious health threat, and requires effective control. To fully utilize an adsorbent and reduce the overall production cost, successive recycling applications become necessary. Here, 3D formicary-like δ-Bi₂O₃ (FL-δ-Bi₂O₃) aerogel adsorbents were synthesized using a one-pot hydrothermal method. In this hybrid structure, abundant flowerlike δ-Bi₂O₃ (MR-δ-Bi₂O₃) microspheres were inlaid into the interconnected ant nest channel, forming a 3D hierarchical structure, which is applied as an efficient adsorbent with easy recovery for radioiodine removal. Notably, the FL-δ-Bi₂O₃ aerogel adsorbent exhibited a very high uptake capacity of 2.04 mmol/g by forming an insoluble Bi₄I₂O₅ phase. Moreover, the FL-δ-Bi₂O₃ worked in a wide pH range of 4–10 and displayed fast uptake kinetics and excellent selectivity due to the 3D porous interconnected network and larger specific surface area. Importantly, the recycling process is easy, using only tweezers to directly move the 3D aerogel adsorbents from one reaction system to another. Therefore, the FL-δ-Bi₂O₃ aerogel may be a promising practical adsorbent for the selective capture of radioactive iodide