Slice Visualization for Imaging Nanocluster Transformations

Abstract

Metal nanoclusters have served as an emerging class of modular nanomaterials. Several efficient strategies have been proposed for transforming cluster precursors into new nanoclusters with customized structures and enhanced performance. However, such nanocluster transformations have still been in a “blind box” state, meaning that the existing intermediates were hard to track with atomic precision. Herein, we present a “slice visualization” approach for in-depth imaging of the nanocluster transformation from Au1Ag24(SR)18 to Au1Ag30(SR)20. With this approach, two cluster intermediates, namely, Au1Ag26(SR)19 and Au1Ag28(SR)20, were monitored with atomic precision. The four nanoclusters constituted a correlated Au1Ag24+2n (n = 0, 1, 2, and 3) cluster series with comparable structural featuresthe same Au1Ag12 icosahedral kernel but evolutionary peripheral motif structures. The mechanism of nanocluster structure growth was mapped in detailinsertion of Ag2(SR)1 or Ag-induced assembly of surface subunits. The presented “slice visualization” approach not only contributes an ideal cluster platform for in-depth investigations of structure–property correlations but also hopefully acts as a powerful means for obtaining clear information on nanocluster structure evolution.

pH-Switchable phenylalanine-templated copper nanoclusters: CO2 probing and efficient peroxidase mimicking activity

“…45 Our as-prepared B-CuNCs exhibit a very large Stokes shift ( λ em at 410 nm upon excitation of 290 nm), characteristic of MNCs, which is a typical signature of the presence of LMCT interaction in the CuNCs. 46 Apart from this, HR-TEM analysis reveals that the sizes of both the CuNCs are in the nanometer domain, and hence the emission of CuNCs appears because of the combined effect of both core-based PL and LMCT-based PL.…”

“…The appearance of an isosbestic point (or isoabsorption point) at 260 nm in the absorption spectra further confirms the pH-induced transformation of one species to another species through a single transition state formation. 46 The nature of the absorption profiles of the two CuNCs is considerably different as shown in Fig. 4b.…”

Self-assembled copper nanoclusters used to mimic peroxidase for glucose detection

“…Hence, they have great potential for NCs species with different congurations. [9][10][11][12][13] The metal core and surface ligands inuence the properties of metal NCs. Compared with the noble metals Au and Ag, the metal Cu is widely used in industries because it has higher conductivity, is cheaper, and is relatively abundant.…”

“Visualizing” the partially reversible conversion of gold nanoclusters via the Au23(S-c-C6H11)17 intermediate

“…However, the high reactivity and labile nature of the transformation intermediates make their isolation and characterization far-fetched and reports on the same are seldom found. 24–27 Additionally, understanding the intriguing ligand effects on the atomically precise metal NCs has always been at the forefront of comprehending the structure–property correlation in these nanomaterials. Even the slightest change in the surface protecting motifs has shown to cause radical changes in the electronic structure and thereby the core-to-shell electronic coupling in metal NCs.…”