Liquid-Phase Exfoliation of Bismuth Telluride Iodide (BiTeI): Structural and Optical Properties of Single-/Few-Layer Flakes.

Bismuth telluride halides (BiTeX) are Rashba-type crystals with several potential applications ranging from spintronics and nonlinear optics to energy. Their layered structures and low cleavage energies allow their production in a two-dimensional form, opening the path to miniaturized device concepts. The possibility to exfoliate bulk BiTeX crystals in the liquid represents a useful tool to formulate a large variety of functional inks for large-scale and cost-effective device manufacturing.

Nickel-Iron Layered Double Hydroxide Dispersions in Ethanol Stabilized by Acetate Anions.

This work reports a method to obtain stable dispersions of nickel-iron layered double hydroxide (NiFe-LDH) nanosheets in ethanol by exposing the as-synthetized bulk NiFe-LDH to a sodium acetate solution or by adding acetate and citrate anions inside the reaction mixture. In the case of citrate-containing NiFe-LDH, the formation of single-layer nanosheets is confirmed by X-ray diffraction and atomic force microscopy measurements. Lastly, the effect of acetate ions on the electrocatalytic activity of NiFe-LDH is discussed for the oxygen evolution reaction.

Two-Dimensional Gallium Sulfide Nanoflakes for UV-Selective Photoelectrochemical-type Photodetectors.

Two-dimensional (2D) transition-metal monochalcogenides have been recently predicted to be potential photo(electro)catalysts for water splitting and photoelectrochemical (PEC) reactions. Differently from the most established InSe, GaSe, GeSe, and many other monochalcogenides, bulk GaS has a large band gap of ∼2.5 eV, which increases up to more than 3.

Electrochemically Deposited NiO Films as a Blocking Layer in -Type Dye-Sensitized Solar Cells with an Impressive 45% Fill Factor.

The enhancement of photoelectrochemical conversion efficiency of -type dye-sensitized solar cells (-DSSCs) is necessary to build up effective tandem devices in which both anode and cathode are photoactive. The efficiency of a -type device (2.5%) is roughly one order of magnitude lower than the -type counterparts (13.