A simple and rapid microwave-assisted wet chemical route was developed for the preparation of Sb 2 Te 3 hexagonal single-crystalline nanoplates with edge length of hundreds of nanometers. The products were characterized with X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and selected area electron diffraction (SAED) techniques. The reaction mechanism was proposed and the effects of alkali, solvents, and stimulating factors such as ultrasonic wave and solvothermal process were studied. The effects of some additives were also discussed, and PVP (polyvinyl pyrrolidone) was found to be able to regularize and diminish the nanoplates.

evolution and energy storage than its semiconducting counterpart. [3] Motivated by these fundamental understanding, diverse attempts have been recently made to synthesize 1T-phase MoX 2 , mainly focusing on the strategies including alkali metal intercalation, [4] hydrothermal reaction, [3a,5] plasma hot electron transfer, [6] mechanical strain, [7] and electron-beam irradiation, etc. [8] However, theoretical and experimental results indicate that 1T phase of MX 2 is inherently unstable and easily converted to thermodynamically stable 2H phase. [9] To this end, a strategy to fabricate and stabilize 1T-MoS 2 via electron injection from conductive carbon [10] and metal, etc. [1c,6] was developed, opening up opportunities for controllable synthesis and practical application of 1T-MoX 2 nanostructures.One of the intriguing applications of 1T-MoX 2 is to catalyze electrochemical water splitting for clean hydrogen production due to its earth-abundant nature and high intrinsic activity for H 2 formation from adsorbed hydrogen species H ad . [11] It is known that hydrogen evolution reaction (HER) in alkaline media involves Volmer step-water dissociation and formation of reactive H ad , followed by either Heyrovsky step or Tafel step. Water dissociation needs extra energy to break HOH bond, leading to the slower HER kinetics in alkaline media than acidic media. Constructing heterostructure with a component for accelerating water dissociation would promote the overall reaction rates for HER in alkaline media. [12] The crystal phase significantly affects the properties and functions of molybdenum dichalcogenides (MoX 2 ). Phase-engineered synthesis is challenging for constructing metallic-phase 1T-MoX 2 for better electrocatalysis than their semiconducting counterparts. Here, 1T-MoSe 2 nanosheet arrays are successfully prepared on metallic NiSe nanowires to couple the synergistic effects of efficient hydrogen formation and water dissociation for hydrogen evolution reaction (HER). Systematic investigations reveal that the electronic injection from NiSe to MoSe 2 induces the phase transition from 2H-to metallic 1T-phase. Benefiting from the phase engineering for enhancing intrinsic activity, the heterostructure for synergistically boosting water dissociation-as well as hierarchical 3D catalyst configuration for abundant active sites, efficient electron transport and mass transfer-the obtained shell/core 1T-MoSe 2 /NiSe exhibits superior HER activity and durability. Such a strategy paves a new way for fabricating various 1T-MoX 2 -based heterostructures for diverse applications. Electronic InjectionThe ORCID identification number(s) for the author(s) of this article can be found under https://doi.Crystal phase-controlled synthesis of transition-metal dichalcogenides (TMDs) has emerged for tuning their physicochemical properties. [1] Group-VI TMDs such as molybdenum dichalcogenides (MoX 2 , X = S or Se) exist in several polymorphs including 2H and 1T phases according to the arrangement of X atoms. The stable 2H phase ...

Although a variety of passivators have been researched to passivate the defects, sufficient defect passivation still remains a challenge to further elevate the efficiency of perovskite light emitting diodes (PeLEDs). Herein, we report that the BMIM + ions of the 1-butyl-3methylimidazolium tetrafluoroborate (BMIMBF 4 ) ionic liquid have effective passivation interaction to the Pb-related defects. And, the spontaneously formed targeted distribution of the BMIM + ions on the crystal surface and film top surface of the polycrystalline perovskite layers well matches the defect site distribution, resulting in the defects being sufficiently passivated. As a result, sufficient defect passivation of ionic liquid enables the photoluminescence quantum yields (PLQYs) to reach 100% and the maximum external quantum efficiency (EQE) of the PeLEDs increased to 22.9%. This work initializes the selection of the promising ionic liquid passivators for high efficiency PeLEDs and highlights the critical role of the passivator spatial distribution for sufficient defect passivation.

Fe/P dual doping synergistically improves the activity and durability of CoS2 polycrystalline nanowire arrays towards efficient hydrogen production.

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The confinement effect is applied to tandem catalysis in Au@Cu2O yolk–shell nanoparticles to promote the efficient and selective reduction of CO2 to ethanol at low potential.

In this work, a feasible method was proposed to prepare MoS 2 -based plasmonic hybrid systems with high photoluminescence (PL) emission enhancement. The enhancement effect of plasmonic hybrids on the PL emission of MoS 2 has been systematically studied on MoS 2 /Ag spherical nanoparticle (SP) hybrid systems with different architectures by changing the stacking position of Ag SPs. It is demonstrated that the sandwich-like hybrid composed of monolayer MoS 2 and dielectric Al 2 O 3 layer between two layers of Ag SPs has the highest PL enhancement. Remarkably, after adding an Al 2 O 3 layer under MoS 2 , the PL intensity enhancement up to 209 times was achieved in the sandwich-like hybrid system. Compared with the hybrid with single-layer SPs, the sandwich-like hybrid system with double-layer Ag SPs exhibited an obvious blue shift as a result of the selective enhancement of the A 0 exciton in MoS 2 . These results demonstrate that MoS 2 /Ag SP hybrid nanosystems have significant implications for sensing and photoelectronic devices.

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