Unexpected Magnetic Moments in Manganese-doped (CdSe)13 Nanoclusters: Role of Ligands, Angewandte Chemie International Edition 64, e202420257(2025)
Guo-Lun Huang, Ko-Yu Ting, Nagaraju Narayanam, Dong-Rong Wu, Tzung-En Hsieh, Kai-Chih Tsai, Da-Wei Yang, Qi-Xun Tang, Bo-Kai Su, Yu-Ting Kang, Shing-Jong Huang, Ching-Hsiang Chen, Yuan-Pin Chang, Lan-Sheng Yang, Yu-Chiang Chao, Elise Yu-Tzu Li*, and Yi-Hsin Liu*
2025/11/24
This study explores the enhancement in magnetic and photoluminescence properties of Mn2+-doped (CdSe)13 nanoclusters, significantly influenced by the introduction of paramagnetic centers through doping, facilitated by optimized precursor chemistry and precisely controlled surface ligand interactions. Using a cost-effective and scalable synthesis approach with elemental Se and NaBH4 (Se-NaBH4) in n-octylamine, we tailored bonding configurations (Cd−O, Cd−N, and Cd−Se) on the surface of nanoclusters, as confirmed by EXAFS analysis. These bonding configurations allowed for tunable Mn2+-doping with tetrahedral coordination, further stabilized by hydrogen-bonded acetate ligands, as evidenced by 13C NMR and IR spectroscopy. Mulliken charge analysis indicates that the charge redistribution on Se2− suggests electron transfer between surface ligands and the nanocluster, contributing to spin fluctuations. These tailored configurations markedly increased the nanoclusters′ magnetic susceptibility and photoluminescence efficiency. The resulting nanoclusters demonstrated a clear concentration-dependent response in emission lifetimes and intensities upon exposure to magnetic field effects (MFE) and spin-spin coupling, alongside a large magnetic moment exceeding 40 μB at 180 K. These findings highlight the potential of these nanoclusters for magneto-optical devices and spintronic applications, showcasing their tunable magnetic properties and exciton dynamics.