We have studied the magneto-electroluminescence (MEL) response in light emitting diodes based on 2D-(PEA)PbI and 3D-MAPbI hybrid organic-inorganic perovskites at cryogenic temperatures. We found that the MEL is negative, i.e., the EL decreases with the applied field strength, B. In addition, the MEL(B) response has a Lorentzian line shape whose width depends on the perovskite used. We interpret the MEL(B) response using the "Δg mechanism" in which the spin of the injected electron-hole (e-h) pairs oscillates between singlet and triplet configurations due to different precession frequencies of the electron and hole constituents that originate from the difference, Δg, in the electron and hole gyromagnetic constants, g. In this model, the MEL(B) linewidth is inversely proportional to the spin lifetime and Δg. The model used is validated by directly measuring the spin lifetime of photogenerated e-h pairs using the circularly polarized pump-probe transmission technique with 100 fs resolution.
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ACS Nano
January 2025
Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States.
Polymeric membranes with great processability are attractive for the H/CO separation required for hydrogen production from renewable biomass with carbon capture for utilization and sequestration. However, it remains elusive to engineer polymer architectures to obtain desired sub-3.3 Å ultramicropores to efficiently sieve H from CO.
View Article and Find Full Text PDFNPG Asia Mater
May 2024
Department of Chemistry, KU Leuven, Leuven, Belgium.
All-inorganic lead halide perovskites (LHPs) and their use in optoelectronic devices have been widely explored because they are more thermally stable than their hybrid organic‒inorganic counterparts. However, the active perovskite phases of some inorganic LHPs are metastable at room temperature due to the critical structural tolerance factor. For example, black phase CsPbI is easily transformed back to the nonperovskite yellow phase at ambient temperature.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Beijing Institute of Technology, 5# Zhongguancun Street, CHINA.
Zn-MnO2 batteries with two-electron transfer harvest high energy density, high working voltage, inherent safety, and cost-effectiveness. Zn2+ as the dominant charge carriers suffer from sluggish kinetics due to the strong Zn2+-MnO2 coulombic interaction, which is also the origin of pestilent MnO2 lattice deformation and performance degradation. Current studies particularly involve H+ insertion-dominating chemistry, where the long-term cycle stability remains challenging due to the accumulative Zn2+ insertion and structural collapse.
View Article and Find Full Text PDFAdv Mater
January 2025
Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing, 100044, China.
Hybrid excitons formed via resonant hybridization in 2D material heterostructures feature both large optical and electrical dipoles, providing a promising platform for many-body exciton physics and correlated electronic states. However, hybrid excitons at organic-inorganic interface combining the advantages of both Wannier-Mott and Frenkel excitons remain elusive. Here, hybrid excitons are reported in the copper phthalocyanine/molybdenum diselenide (CuPc/MoSe) heterostructure (HS) featuring strong molecular orientation dependence by low-temperature photoluminescence and absorption spectroscopy.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212003, China. Electronic address:
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