Arsenic Monolayers Formed by Zero-Dimensional Tetrahedral Clusters and One-Dimensional Armchair Nanochains
Guowei Liu, Shao-Gang Xu, Yaping Ma, Xiji Shao, Wenqi Xiong, Xuefeng Wu, Shuxuan Zhang, Chenwei Liao, Congrun Chen, Xixian Wang, Shengjun Yuan, Weifeng Zhang, Jiong Lu, Hu Xu, Kedong Wang, Xudong Xiao
Abstract
One-dimensional (1D) arsenene nanostructures are predicted to host a variety of interesting physical properties including antiferromagnetic, semiconductor–semimetal transition and quantum spin Hall effect, which thus holds great promise for next-generation electronic and spintronic devices. Herein, we devised a surface template strategy in a combination with surface-catalyzed decomposition of molecular As4 cluster toward the synthesis of the superlattice of ultranarrow armchair arsenic nanochains in a large domain on Au(111). In the low annealing temperature window, zero-dimensional As4 nanoclusters are assembled into continuous films through intermolecular van der Waals and molecule–substrate interactions. At the elevated temperature, the subsequent surface-assisted decomposition of molecular As4 nanoclusters leads to the formation of a periodic array of 1D armchair arsenic nanochains that form a (2 × 3) superstructure on the Au(111) surface. These ultranarrow armchair arsenic nanochains are predicted to have a small bandgap of ∼0.50 eV, in contrast to metallic zigzag chains. In addition, the Au-supported arsenic nanochains can be flipped to form a bilayer structure through tip indentation and manipulation, suggesting the possible transfer of these nanochains from the substrate. The successful realization of arsenic nanostructures is expected to advance low-dimensional physics and infrared optoelectronic nanodevices.