98%
921
2 minutes
20
Light-driven spin hyperpolarization of organic molecules is a crucial technique for spin-based applications such as quantum information science (QIS) and dynamic nuclear polarization (DNP). Synthetic chemistry provides the design of spins with atomic precision and enables the scale-up of individual spins to hierarchical structures. The high designability and extended pore structure of metal-organic frameworks (MOFs) can control interactions between spins and guest molecules. However, the effective design of polarizing radical electron spins by photoexcitation in MOFs has been unexplored. Here, we show that it is possible to effectively hyperpolarize radical electron spins by harvesting mobile excitons in MOFs. As a proof of concept, we introduce 4-carboxy TEMPO molecules as electron spins into MOF-525, which contains an array of porphyrin chromophores, and demonstrate that this light-harvesting MOF system generates a spin-polarized excited quartet state and doublet ground state even by doping a small amount of electron spins. The current material design leads to the creation of highly spin-polarized nanospaces that can be used for quantum sensing and DNP by efficiently generating high-spin polarization in MOFs doped with small amounts of electron spins to prevent spin relaxation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/jacs.4c14916 | DOI Listing |
J Phys Chem A
September 2025
Department of Chemistry, Institute for Quantum Information Research and Engineering, and Center for Molecular Quantum Transduction, Northwestern University, Evanston, Illinois 60208-3113, United States.
Light-driven formation of radical ion pairs that occurs much faster than their electron spin dynamics results in correlated spins whose coherence properties can be used as a quantum-based electric field sensor. This results from the radical ion pair having charge and spin distributions that track one another. Thus, electric field induced changes in the distance between the two charges are reflected in the spin-spin distance that can be measured directly using out-of-phase electron spin echo envelope modulation (OOP-ESEEM), a pulse-EPR technique.
View Article and Find Full Text PDFACS Omega
September 2025
Nanohybrids and Innovation Coating Research Group (NHIC), National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Khlong Luang, Pathumthani 12120, Thailand.
Using leaf fibers from pineapple (PALFs) as a model dual-purpose plant, we deliberately explore the effect of bio- and semibiobased treatment using xylanase, cellulase, and a mixture of pectinase and amylase. We assess these treatments for their potential to selectively and precisely remove lignocellulosic components. Additionally, we examine how they modify the relative content of cellulose, hemicellulose, and lignin, as these are key factors affecting the physical appearance, dimensional structures, and mechanical integrity.
View Article and Find Full Text PDFAdv Mater
September 2025
School of Chemistry and Biochemistry, School of Materials Science and Engineering, Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
Molecular spin systems that can be chemically tuned, coherently controlled, and readily integrated within devices remain central to the realization of emerging quantum technologies. Organic high-spin materials are prime candidates owing to their similarity in electronic structure to leading solid-state defect-based systems, light element composition, and the potential for entanglement and qubit operations mediated through spin-spin exchange. However, the inherent instability of these species precludes their rational design, development, and application.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
Department of Chemistry, Indian Institute of Technology, Guwahati, Assam, 781039, India.
Metalloenzymes activate molecular oxygen within their catalytic cycles to generate a reactive species capable of substrate transformation. In many iron-containing enzymes, it is a high-valent iron(IV)-oxo complex that is synthesized from an iron(III)-alkylperoxo intermediate, although direct observation and characterization of such species have remained elusive, leaving their mechanistic role uncertain. To address this gap in our understanding, we present here the synthesis, comprehensive characterization, and reactivity of a novel thioether-ligated iron(III)-alkylperoxo complex supported by the ligand 2-((2-(pyridin-2-yl)ethyl)thio)-N,N-bis(pyridin-2-ylmethyl)ethan-1-amine.
View Article and Find Full Text PDFJ Hazard Mater
September 2025
Institute of Pollution Control and Environmental Health, and School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China. Electronic address:
This study presents the first experimental evidence of biochar (BC) aerosol generation via raindrop impact on amended soils, combining controlled rainfall simulations with year-long field monitoring of atmospheric particulates from a BC-treated plot (2.0 wt%). Microscopic and isotopic analyses confirmed BC incorporation in total suspended particles (TSP), accounting for 15.
View Article and Find Full Text PDF