Galchenko Michael, Black Andrés, Heymann Leonard, Klinke Christian
Institute of Physical Chemistry, University of Hamburg, Martin-Luther-King Platz 6, 20146, Hamburg, Germany.
Department of Chemistry, Swansea University, Singleton Park, Swansea, SA2 8PP, UK.
Adv Mater. 2019 May;31(18):e1900684. doi: 10.1002/adma.201900684. Epub 2019 Mar 25.
Quantum-confined Au nanoclusters exhibit molecule-like properties, including atomic precision and discrete energy levels. The electrical conductivity of Au nanocluster films can vary by several orders of magnitude and is determined by the strength of the electronic coupling between the individual nanoclusters in the film. Similar to quantum-confined, semiconducting quantum dots, the electrical coupling in films is dependent on the size and structure of the Au core and the length and conjugation of the organic ligands surrounding it. Unlike quantum dots, however, semiconducting transport has not been reported in Au nanocluster films. Here, it is demonstrated that through a simple yet careful choice of cluster size and organic ligands, stable Au nanocluster films can electronically couple and become semiconducting, exhibiting electric field effect and photoconductivity. The molecule-like nature of the Au nanoclusters is evidenced by a hopping transport mechanism reminiscent of doped, disordered organic semiconductor films. These results demonstrate the potential of metal nanoclusters as a solution-processed material for semiconducting devices.
量子限域金纳米团簇表现出类似分子的性质，包括原子精度和离散能级。金纳米团簇薄膜的电导率可以变化几个数量级，并且由薄膜中各个纳米团簇之间的电子耦合强度决定。与量子限域的半导体量子点类似，薄膜中的电耦合取决于金核的大小和结构以及围绕它的有机配体的长度和共轭程度。然而，与量子点不同的是，金纳米团簇薄膜中尚未报道半导体输运现象。在此，通过对团簇尺寸和有机配体进行简单而谨慎的选择，证明了稳定的金纳米团簇薄膜能够发生电子耦合并成为半导体，表现出电场效应和光电导性。金纳米团簇类似分子的性质由一种跳跃输运机制所证明，这种机制让人联想到掺杂的、无序的有机半导体薄膜。这些结果证明了金属纳米团簇作为半导体器件溶液加工材料的潜力。
