Lanthanide Double Perovskite Nanocrystals with Emissions Covering the UV‐C to NIR Spectral Range

Advanced Optical Materials · 2023 · 70 citations

• Materials science
• Optoelectronics
• Nanotechnology

Abstract Lead halide perovskite nanocrystals (NCs) have recently drawn considerable attention in the fields of materials science and nanotechnology. However, a major drawback of these NCs is the reliance on toxic lead, which hinders widespread application. Herein, a new class of lead‐free perovskite NCs, that is, lanthanide double perovskite (Ln‐DP) NCs, with f‐orbital‐induced optical properties, is introduced. The Pr‐, Ce‐, Tb‐, Eu‐, Sm‐, and Yb‐based Ln‐DP NCs display narrow d→f and f→f emissions ranging from the UV‐C to the near‐infrared spectral region. Experimental data and calculations reveal that the emissive Ln‐DP NCs exhibit small molecule‐like electronic absorptions: f→d atomic transitions or ligand‐to‐metal charge transfer transitions. Last, it is demonstrated that by alloying Ln compositions in the DP NCs, new materials with unique and improved optical properties can be obtained. These Ln‐DP NCs are promising for optical sensing and lighting, and as components in optoelectronic and/or magneto‐fluorescent devices.

Is Less More? Influence of the Coordination Geometry of Copper(II) Picolinate Chelate Complexes on Metabolic Stability

Inorganic Chemistry · 2020 · 24 citations

• Chemistry
• Crystallography
• Inorganic chemistry

A growing number of copper(II) complexes have been identified as suitable candidates for biomedical applications. Here, we show that the biocompatibility and stability of copper(II) complexes can be tuned by directed ligand design and complex geometry. We demonstrate that azamacrocycle-based chelators that envelope copper(II) in a five-coordinate, distorted trigonal-bipyramidal structure are more chemically inert to redox-mediated structural changes than their six-coordinate, Jahn-Teller-distorted counterparts, as evidenced by electrochemical, crystallographic, electron paramagnetic resonance, and density functional theory studies. We further validated our hypothesis of enhanced inertness in vitro and in vivo by employing Cu-64 radiolabeling of bifunctional analogues appended to a prostate-specific membrane antigen targeting dipeptide. The corresponding Cu-64 complexes were tested for stability in vitro and in vivo, with the five-coordinate system demonstrating the greatest metabolic stability among the studied picolinate complex series.