title: Weak Van der Waals Stacking, Wide-Range Band Gap, and Raman Study on Ultrathin Layers of Metal Phosphorus Trichalcogenides.
abstract: 2D semiconducting metal phosphorus trichalcogenides, particularly the bulk crystals of MPS3 (M = Fe, Mn, Ni, Cd and Zn) sulfides and MPSe3 (M = Fe and Mn) selenides, have been synthesized, crystallized and exfoliated into monolayers. The Raman spectra of monolayer FePS3 and 3-layer FePSe3 show the strong intralayer vibrations and structural stability of the atomically thin layers under ambient condition. The band gaps can be adjusted by element choices in the range of 1.3-3.5 eV. The wide-range band gaps suggest their optoelectronic applications in a broad wavelength range. The calculated cleavage energies of MPS3 are smaller than that of graphite. Therefore, the monolayers used for building of heterostructures by van der Waals stacking could be considered as the candidates for artificial 2D materials with unusual ferroelectric and magnetic properties.
authors.affiliation: School of Materials Science & Engineering, Nanyang Technological University , Singapore 639798, Singapore.|Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Ke-zhao
authors.initials: KZ
authors.lastname: Du
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Xing-zhi
authors.initials: XZ
authors.lastname: Wang
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: School of Materials Science & Engineering, Nanyang Technological University , Singapore 639798, Singapore.
authors.forename: Peng
authors.initials: P
authors.lastname: Hu
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: M Iqbal Bakti
authors.initials: MI
authors.lastname: Utama
authors.affiliation: Institute of High Performance Computing, Agency for Science, Technology and Research , 1 Fusionopolis Way, #16-16 Connexis, Singapore 138632, Singapore.
authors.forename: Chee Kwan
authors.initials: CK
authors.lastname: Gan
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.|NOVITAS, Nanoelectronics Centre of Excellence, School of Electrical and Electronic Engineering, Nanyang Technological University , Singapore 639798, Singapore.
authors.forename: Qihua
authors.initials: Q
authors.lastname: Xiong
authors.affiliation: School of Materials Science & Engineering, Nanyang Technological University , Singapore 639798, Singapore.
authors.forename: Christian
authors.initials: C
authors.lastname: Kloc
keywords: Raman spectroscopy; band gap; cleavage energy; metal phosphorus trichalcogenides; two-dimensional semiconductors