مشخصه‌یابی و سنتز آسان نانو ورق‌های فوق‌نازک MoS2 (مولیبدن دی‌سولفید)

ABSTRACT Facile synthesis and characterization of ultrathin MoS2 (Molybdenum disulfide) nanosheets

During the past decades, MoS2, as one member of inorganic transition metal sulfides, has elicited numerous studies because of its unique layered structure and related interesting functional properties. The layered structure consists of strong covalent bonding between Mo–S atomic but weak Van der Waals attraction between lattice layers [1,2]. This unique anisotropic layered structure result in excellent optical, electronic and mechanical properties and wide applications such as catalysts [3], lubricants [4], photoconductors [5], lithium ion battery anodes [6], and hydrogen storage [7].

To date, MoS2 has been reported with different morphologies including nanotubes [8], fullerene-like nanoparticles [1,2], nanoplates [9,10], nanorods [11], nanoflowers [12], nanowires [13] and nanospheres [14]. Recently, ultrathin MoS2 nanosheets have attracted considerable attention due to its extraordinary electrochemical properties. And various methods have been reported on the synthesis of ultrathin MoS2 nanosheets, including scotch tape based micromechanical exfoliation [15], intercalation assisted exfoliation [16], liquid exfoliation [17], physical vapor deposition [18], and hydrothermal synthesis [19]. However, up to now, it is still desirable to develop a facile and scalable strategy to produce ultrathin MoS2 nanosheets on a large scale in order to realize their practical applications.

Herein, ultrathin MoS2 nanosheets with the thickness of 5–10 nm were successfully synthesized through a facile and reproducible gas– solid reaction approach using MoO3 and thiourea as starting materials and the effect of temperature on the morphologies of the as-prepared MoS2 samples was investigated. Furthermore, a possible formation mechanism for the MoS2 nanosheets has been discussed in detail.