posted on 2024-03-04, 08:22authored byChunwei Dong, Xin Song, Bashir E. Hasanov, Youyou Yuan, Luis Gutiérrez-Arzaluz, Peng Yuan, Saidkhodzha Nematulloev, Mehmet Bayindir, Omar F. Mohammed, Osman M. Bakr
Organic–inorganic atomically precise nanoclusters
provide
indispensable building blocks for establishing structure–property
links in hybrid condensed matter. However, robust glasses of ligand-protected
nanocluster solids have yet to be demonstrated. Herein, we show [Cu4I4(PR3)4] cubane nanoclusters
coordinated by phosphine ligands (PR3) form robust melt-quenched
glasses in air with reversible crystal–liquid–glass
transitions. Protective phosphine ligands critically influence the
glass formation mechanism, modulating the glasses’ physical
properties. A hybrid glass utilizing ethyldiphenylphosphine-based
nanoclusters, [Cu4I4(PPh2Et)4], exhibits superb optical properties, including >90% transmission
in both visible and near-infrared wavelengths, negligible self-absorption,
near-unity quantum yield, and high light yield. Experimental and theoretical
analyses demonstrate the structural integrity of the [Cu4I4(PPh2Et)4] nanocluster, i.e.,
iodine-bridged tetranuclear cubane, has been fully preserved in the
glass state. The strong internanocluster CH−π interactions
found in the [Cu4I4(PPh2Et)4] glass and subsequently reduced structural vibration account for
its enhanced luminescence properties. Moreover, this highly transparent
glass enables performant X-ray imaging and low-loss waveguiding in
fibers drawn above the glass transition. The discovery of “nanocluster
glass” opens avenues for unraveling glass formation mechanisms
and designing novel luminescent glasses of well-defined building blocks
for advanced photonics.