Experimental Realization and Computational Investigations of B2S2 as a New 2D Material with Potential Applications.

A new two-dimensional material B2S2 has been successfully synthesized for the first time and validated using first-principles calculations, with fundamental properties analyzed in detail. B2S2 has a similar structure as transition-metal dichalcogenides (TMDs) such as MoS2, and the experimentally prepared free-standing B2S2 nanosheets show a uniform height profile lower than 1 nm. A thickness-modulated and unique oxidation-level dependent band gap of B2S2 is revealed by theoretical calculations, and vibration signatures are determined to offer a practical scheme for the characterization of B2S2. It is shown that the functionalized B2S2 is able to provide favorable sites for lithium adsorption with low diffusion barriers, and the prepared B2S2 shows a wide band photoluminescence response. These findings offer a feasible new and lighter member for the TMD-like 2D material family with potential for various aspects of applications, such as an anode material for Li-ion batteries and electronic and optoelectronic devices.

High-Yield Production of Few-Layer Graphene via New-fashioned Strategy Combining Resonance Ball Milling and Hydrothermal Exfoliation.

Graphene shows great potential applications in functional coating, electrodes, and ultrasensitive sensors, but high-yield and scalable preparation of few-layer graphene (FLG) by mechanical exfoliation method is still a formidable challenge. In this work, a novel two-step method for high-yield preparation of FLG is developed by combining resonance ball milling and hydrothermal treatment. During the resonance ball milling process, the utilization of magnetic Fe3O4 nanoparticles as a new "particle wedge" is beneficial to facilitate fragment and delamination of graphitic layers. In addition, further hydrothermal treatment can enhance ball milling product (BMP) exfoliation because of the shear force driven by the Brownian motion of various molecules at high temperature and high pressure. As expected, the two-step method can have high exfoliation efficiency up to 92% (≤10 layers). Moreover, the FLG nanosheet ink can easily achieve the formation of FLG coatings on the surface of various substrates, resulting in good electrical conductivity, which possesses potential applications in various fields including functional coating, energy storages, and electrochemical sensors, etc. Our work provides a new-fashioned strategy for mechanical large-scale production of graphene.