Cage-Like Nanoclusters of ZnO Probed by Time-Resolved Photoelectron Spectroscopy and Theory

Abstract

Zinc oxide nanoclusters have been predicted as promising building blocks for cluster-assembled materials with unprecedented properties. Here, for the first time these clusters are probed by time-resolved photoelectron spectroscopy and characterized in detail by density functional theory. Their validity as building blocks for cluster-assembled materials is confirmed via rigid cage-like structures facilitating three-dimensional aggregation in combination with large band gaps that are nevertheless significantly lower than any known ZnO polymorph. In addition, electron-hole pair localization in the excited state of the cluster anions combined with their structural rigidity leads to extraordinary long-lived states above the band gap virtually independent of the cluster size, defying the rule "every atom counts".

The Zn12O12 cluster-assembled nanowires as a highly sensitive and selective gas sensor for NO and NO2

“…Recently, Zn 12 O 12 cluster has been probed by time-resolved photoelectron spectroscopy 52 , 53 , which further demonstrates that Zn 12 O 12 cluster is a promising building block for cluster-assembled materials with tailed properties. In previous work, we have proposed one growth path of Zn 12 O 12 cluster-cluster coalescence, and predicted that assembly can form by attaching a Zn 12 O 12 cage on a hexagonal site 50 .…”

Superconductivity in an expanded phase of ZnO: anab initiostudy

“…Theoretical [28][29][30] and experimental studies [31] agree that the (ZnO) 12 cluster is stable and energetically favored. Furthermore, very recent works point to the existence of ZnO cage-like nanostructures using photoelectron spectroscopy together with DFT calculations [32]. The (ZnO) 12 clusters identified in [32] are very similar to the building blocks of the sodalite structure.…”

“…Furthermore, very recent works point to the existence of ZnO cage-like nanostructures using photoelectron spectroscopy together with DFT calculations [32]. The (ZnO) 12 clusters identified in [32] are very similar to the building blocks of the sodalite structure. Finally, another experimental paper shows the existence of fullerene-like structures of ZnO produced by laser ablation and studied by time of flight mass spectroscopy [33].…”

Theoretische Chemie 2014

“…Mit ihrer einstellbaren Bandlücke hätten diese hypothetischen Materialien Potenzial für photokatalytische Anwendungen. Jedoch wurde erst kürzlich die Existenz der dazu benötigten hochsymmetrischen, käfigartigen Clusterbausteine durch eine Kombination von experimentellen und theoretischen Untersuchungen bestätigt 3_19…”