Herein we present a Ligand Field Density Functional Theory (LFDFT) based methodology for the analysis of the 4f(n)→ 4f(n-1)5d(1) transitions in rare earth compounds and apply it for the characterization of the 4f(2)→ 4f(1)5d(1) transitions in the quantum cutter Cs2KYF6:Pr(3+) with the elpasolite structure type. The methodological advances are relevant for the analysis and prospection of materials acting as phosphors in light-emitting diodes. The positions of the zero-phonon energy corresponding to the states of the electron configurations 4f(2) and 4f(1)5d(1) are calculated, where the praseodymium ion may occupy either the Cs(+)-, K(+)- or the Y(3+)-site, and are compared with available experimental data. The theoretical results show that the occupation of the three undistorted sites allows a quantum-cutting process. However size effects due to the difference between the ionic radii of Pr(3+) and K(+) as well as Cs(+) lead to the distortion of the K(+)- and the Cs(+)-site, which finally exclude these sites for quantum-cutting. A detailed discussion about the origin of this distortion is also described.
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Angew Chem Int Ed Engl
December 2024
Qingdao University of Science and Technology, college of materials science and engineering, Zhengzhou Road 53#, 266042, Qingdao, CHINA.
The catalytic efficiency of natural enzymes depends on the precise electronic interactions between active centers and cofactors within a three-dimensional (3D) structure. Single-atom nanozymes (SAzymes) attempt to mimic this structure by modifying metal active sites with molecular ligands. However, SAzymes struggle to match the catalytic efficiency of natural enzymes due to constraints in active site proximity, quantity, and the inability to simulate electron transfer processes driven by internal electronic structures of natural enzymes.
View Article and Find Full Text PDFAdv Mater
December 2024
Tianjin Key Lab for Rare Earth Materials and Applications, Center for Rare Earth and Inorganic Functional Materials, School of Materials Science and Engineering, National Institute for Advanced Materials, Nankai University, Tianjin, 300350, China.
Currently, there are still obstacles to rationally designing the ligand fields to activate rare-earth (RE) elements with satisfactory intrinsic electrocatalytic reactivity. Herein, axial coordination strategies and nanostructure design are applied for the construction of La single atoms (La-Cl SAs/NHPC) with satisfactory oxygen reduction reaction (ORR) activity. The nontrivial LaNCl motifs configuration and the hierarchical porous carbon substrate that facilitates maximized metal atom utilization ensure high half-wave potential (0.
View Article and Find Full Text PDFFront Bioeng Biotechnol
December 2024
Vascularized Composite Allotransplantation Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.
Introduction: Magnetic nanoparticles (MNPs), particularly iron oxide nanoparticles (IONPs), are renowned for their superparamagnetic behavior, allowing precise control under external magnetic fields. This characteristic makes them ideal for biomedical applications, including diagnostics and drug delivery. Superparamagnetic IONPs, which exhibit magnetization only in the presence of an external field, can be functionalized with ligands for targeted affinity diagnostics.
View Article and Find Full Text PDFJ Mater Chem A Mater
December 2024
Department of Materials Engineering, Ben-Gurion University of the Negev Beer Sheva 8410500 Israel
Zinc ferrite (ZnFeO, ZFO) has gained attention as a candidate material for photoelectrochemical water oxidation. However, champion devices have achieved photocurrents far below that predicted by its bandgap energy. Herein, strong optical interference is employed in compact ultrathin film (8-14 nm) Ti-doped ZFO films deposited on specular back reflectors to boost photoanode performance through enhanced light trapping, resulting in a roughly fourfold improvement in absorption as compared to films deposited on transparent substrates.
View Article and Find Full Text PDFEur J Med Chem
December 2024
Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China. Electronic address:
Targeting the biosynthetic pathway of mycolic acid is highly attractive to researchers in the field of novel anti-tubercular drug development. Pks13-TE is an essential catalytic component in the last assembling step of mycolic acid, and the co-crystal structures of the Pks13-TE-inhibitor complex provide insight into ligand recognition. Based on a structure-guided strategy, N-aryl indole derivatives were designed, synthesized, and evaluated for their antitubercular activities.
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