DJL

Black phosphorus quantum dots (BPQDs) were synthesized using a liquid exfoliation method that combined probe sonication and bath sonication. With a lateral size of approximately 2.6 nm and a thickness of about 1.5 nm, the ultrasmall BPQDs exhibited an excellent NIR photothermal performance with a large extinction coefficient of 14.8 Lg⁻¹ cm⁻¹ at 808 nm, a photothermal conversion efficiency of 28.4 %, as well as good photostability. After PEG conjugation, the BPQDs showed enhanced stability in physiological medium, and there was no observable toxicity to different types of cells. NIR photoexcitation of the BPQDs in the presence of C6 and MCF7 cancer cells led to significant cell death, suggesting that the nanoparticles have large potential as photothermal agents.

A liquid exfoliation method based on a combination of probe sonication and bath sonication was adopted to synthesize black phosphorus quantum dots (BPQDs). These displayed a high extinction coefficient of 14.8 Lg⁻¹ cm⁻¹, a photothermal conversion efficiency of 28.4 %, and good biocompatibility, and can thus be used as highly effective photothermal agents for cancer therapy.

The combination of high-quality Al₂O₃ dielectric and thiol chemistry passivation can effectively reduce the density of interface traps and Coulomb impurities, leading to a significant improvement of the mobility and a transition of the charge transport from the insulating to the metallic regime. A record high mobility of 83 cm² V⁻¹ s⁻¹ (337 cm² V⁻¹ s⁻¹) is reached at room temperature (low temperature) for monolayer WS₂. A theoretical model for electron transport is also developed.

Graphene quantum dots (GQDs) interacting with molybdenum disulfide (MoS₂) monolayers induce an effective photoexcited charge transfer at the interface. Both the photoluminescence (PL) and valley polarization of this GQDs/MoS₂ heterostructure can be modulated under various doping charge densities. The photon–exciton interaction is used to explain and calculate the heterostructure PL control, and is further applied to the valley-polarization tuning.

By plasma-enhanced chemical vapor deposition, a molybdenum disulfide (MoS₂) thin film is synthesized directly on a wafer-scale plastic substrate at below 300 °C. The carrier mobility of the films is 3.74 cm² V⁻¹ s⁻¹. Also, humidity is successfully detected with MoS₂-based sensors fabricated on the flexible substrate, which reveals its potential for flexible sensing devices.

Given that surfactants can control the shape and size of micro-/nanoparticles, they should be able to direct the growth of bulk crystals. This Minireview summarizes recent developments in the application of surfactants for the preparation of new crystalline inorganic materials, including chalcogenides, metal–organic frameworks, and zeolite analogues. The roles of surfactants in different reaction systems are discussed.

Multifaceted media: Since surfactants can control the shape and size of micro-/nanoparticles, they are also able to direct the growth of bulk crystals. Recent developments in the use of surfactants in the preparation of crystalline inorganic materials, including chalcogenides, metal–organic frameworks, and zeolite analogues, are summarized in this Minireview.

The controllable synthesis of black phosphorus quantum dots as ultrasmall photothermal agents is described by P. K. Chu, H. Zhang, X.-F. Yu, and co-workers in their Communication on page 11526 ff. The nanoparticles display a high extinction coefficient of 14.8 Lg⁻¹ cm⁻¹, a photothermal conversion efficiency of 28.4 %, and good biocompatibility, thus demonstrating great potential for photothermal therapy.

Black phosphorus (BP), the latest addition to the family of 2D layered materials, has attracted much interest owing to potential optoelectronics, nanoelectronics, and biomedicine applications. Little is known about its toxicity, such as whether it could be as toxic as white phosphorus. In response to the possibility of BP employment into commercial products and biomedical devices, its cytotoxicity to human lung carcinoma epithelial cells (A549) was investigated. Following a 24 h exposure of the cells with different BP concentrations, cell viability assessments were conducted using water-soluble tetrazolium salt (WST-8) and methylthiazolyldiphenyltetrazolium bromide (MTT) assays. The toxicological effects were found to be dose-dependent, with BP reducing cell viabilities to 48 % (WST-8) and 34 % (MTT) at 50 μg mL⁻¹ exposure. This toxicity was observed to be generally intermediate between that of graphene oxides and exfoliated transition-metal dichalcogenides (MoS₂, WS₂, WSe₂). The relatively low toxicity paves the way to utilization of black phosphorus.

Mostly harmless: The toxicity of black phosphorus (phosphorene), a promising layered material with semiconducting properties, was investigated. The toxicity was found to be very low when compared to graphene-based materials.

Nanocarbon (carbon nanotubes (CNTs) and graphene (GN)) composites attract considerable research interest due to their fascinating applications in many fields. Here, recent developments in the field of in situ chemical vapor deposition (CVD) for the design and controlled preparation of advanced nanocarbon composites are highlighted, specifically, CNT-reinforced bulk structural composites, as well as CNT, GN, and CNT/GN functional composites, together with their practical and potential applications. In situ CVD is a very attractive approach for the fabrication of composites because of its engaging features, such as its simplicity, low-cost, versatility, and tunability. The morphologies, structures, dispersion, and interface of the resulting nanocarbon composites can be easily modulated by varying the experimental parameters (such as temperature, catalysts, carbon sources, templates or template catalysts, etc.), which enables a great potential for the in situ synthesis of high-quality nanocarbons with tailored size and dimension for constructing high-performance composites, which has not yet been achieved by conventional methods. In addition, new trends of the in situ CVD toward nanocarbon composites are discussed.

The in situ chemical vapor deposition (CVD) strategy is a well-known, versatile and powerful tool for directly preparing advanced nanocarbon composites with controllable morphologies, dispersion, and interfaces. The recent progress regarding in situ CVD to construct nano­carbon composites, specifically, carbon-nanotube (CNT)-reinforced bulk structural composites, as well as CNT, graphene (GN), and CNT/GN functional composites, together with their practical and potential applications, are discussed.

A new type of cellular material named Shellular, in which cells are composed of a continuous, smooth-curved shell according to the minimal surface theory, is proposed. Shellular specimens are fabricated using 3D lithography with negative templates and hard coating, and exhibit superb strength and stiffness at densities lower than 10⁻² Mg m⁻³, incorporating benefits from hierarchical structures and constituent materials with nanosized grains.