Doping of bulk silicon and III–V materials has paved the foundation of the current semiconductor industry. Controlled doping of 2D semiconductors, which can also be used to tune their bandgap and type of carrier thus changing their electronic, optical, and catalytic properties, remains challenging. Here the substitutional doping of nonlike element dopant (Mn) at the Mo sites of 2D MoS2 is reported to tune its electronic and catalytic properties. The key for the successful incorporation of Mn into the MoS2 lattice stems from the development of a new growth technology called dual‐additive chemical vapor deposition. First, the addition of a MnO2 additive to the MoS2 growth process reshapes the morphology and increases lateral size of Mn‐doped MoS2. Second, a NaCl additive helps in promoting the substitutional doping and increases the concentration of Mn dopant to 1.7 at%. Because Mn has more valance electrons than Mo, its doping into MoS2 shifts the Fermi level toward the conduction band, resulting in improved electrical contact in field effect transistors. Mn doping also increases the hydrogen evolution activity of MoS2 electrocatalysts. This work provides a growth method for doping nonlike elements into 2D MoS2 and potentially many other 2D materials to modify their properties.

The lateral size of single layer GO that was synthesized by an electrochemically assisted improved Hummers method reached 300 μm.

Nanomaterials with various dimensionalities (e.g., nanowires, nanofilms, two-dimensional materials, and three-dimensional nanostructures) have shown great potential in the recent development of flexible electronics. Conventionally, organic solvents are inevitable while integrating nanomaterials onto flexible substrates, where polymer mediator-assisted transfer techniques are involved. This often damages the flexible substrate and thus hamper the large-scale application of nanomaterials. Here we report a method using watersoluble sugar as a mediator to facilely transfer nanomaterials onto rigid or flexible substrates. This method requires no organic solvent during transfer. More importantly, the morphology and properties of transferred nanomaterials, such as shape, microstructure, resistivity, and transmittance are well preserved on the target substrate. We believe that this universal and rapid transfer method can greatly advance the applications of nanomaterials in the field of flexible devices and beyond. ARTICLE HISTORY

AlxGa1−xAs (x>0.30) double heterostructures are grown by molecular-beam epitaxy (MBE) and the minority-carrier lifetimes are measured by time-resolved photoluminescence. The data indicate that the minority-carrier lifetimes in high aluminum (x>0.30) AlxGa1−xAs grown by MBE are comparable to the previously published lifetimes of material grown by liquid-phase epitaxy. The lifetimes in MBE materials appear to be somewhat larger than those measured in materials grown by metalorganic chemical vapor deposition. Factors affecting AlGaAs minority-carrier lifetime, such as the growth temperature, the aluminum concentration, and the confinement layer composition will be discussed.

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