Organic-inorganic halide perovskite (OIHP) materials through their promising material properties, simple solution processability, low material cost, high photon absorption, carrier mobilities, and tunable band gap are suitable for large area coatings in the fabrication of optical displays, LEDs, photovoltaic cells and photodetectors. However, OIHP stability and shelf life have been limited to date as exposed perovskite films do not survive long in ambient air causing further issues for large scale OIHP based device production and deployment. Accordingly, the inventors have established three-cation material system variants using an innovative single solution thiocyanate (SCN) doped three cation material system allowing tailoring of perovskite grain size and microstructure to minimize degradation from exposure to atmospheric conditions. Further, solvent engineering techniques using the innovative single solution SCN doped three cation material system established by the inventors allow for large area processing, compact OIHP films with large crystal grains (>4 μm), and passivated grain boundaries.

Disclosed is a perovskite light-emitting device with reduced defects in a perovskite thin film. The passivation layer in the perovskite light-emitting device is formed on the upper part of the perovskite thin film to eliminate defects in the perovskite nanocrystalline particles and resolve charge imbalance in the device, thereby improving maximum efficiency and maximum luminance of the light-emitting device.

Provided is a method of producing a metal nanoparticle-oxide support complex structure, in which metal nanoparticles uniform in size are evenly distributed on the surface of oxide supports. A gas sensor with improved gas sensing ability and durability may be provided by using the same.

A lead-free lithium doped potassium sodium niobate piezoelectric ceramic material in powdered form and having a single crystalline phase and uses thereof are described. Methods of making the said piezoelectric ceramic material are also described.

Methods are provided for making halide perovskite thin films. The method may include forming a pattern of islands of a nucleation promoter material onto a substrate; applying onto the substrate and islands a solution which includes a halide perovskite or precursors thereof, to form a coated substrate; and drying the coated substrate to form a crystalline halide perovskite film. Halide perovskite thin films, which may be made by these methods, and LEDs including these films are also provided.

A method of forming a polyolefin-perovskite nanomaterial composite which contains oriented electrically and thermally conductive pathways. The method involves milling a polyolefin with particles of a perovskite nanomaterial, molding to forma composite plate, and subjecting the composite plate to an AC voltage. The AC voltage forms oriented electrically and thermally conductive pathways by partial dielectric breakdown of the composite. The presence of the oriented electrically and thermally conductive pathways gives the polyolefin-perovskite nanomaterial electrical and thermal conductivity and dielectric permittivity higher than the polyolefin alone.

The present disclosure relates to a mixture that includes a perovskite precursor, a solvent, and an additive that includes at least one of a first amine, a ketone, an aldehyde, a non-nucleophilic sterically hindered base, and/or a halogen-containing compound, where, upon removal of the solvent and the additive, the perovskite precursor is capable of being transformed into a perovskite.

Thermochemical storage materials having the general formula A.sub.xA′.sub.1-xB.sub.yB′.sub.1-yO.sub.3-δ, where A=La, Sr, K, Ca, Ba, Y and B=Mn, Fe, Co, Ti, Ni, Cu, Zr, Al, Y, Cr, V, Nb, Mo, are disclosed. These materials have improved thermal storage energy density and reaction kinetics compared to previous materials. Concentrating solar power thermochemical systems and methods capable of storing heat energy by using these thermochemical storage materials are also disclosed.

Disclosed is a self-powered perovskite X-ray detector. The self-powered perovskite X-ray detector according to an embodiment of the present invention has a shape wherein a scintillator converting incident X-rays into visible light is combined with a perovskite photodetector, wherein the scintillator and the perovskite light absorption layer include a perovskite compound represented by Formula 1 below:
A.sub.aM.sub.bX.sub.c  [Formula 1] where A is a monovalent cation, M is a divalent metal cation or a trivalent metal cation, X is a monovalent anion, a+2b=c when M is a divalent metal cation, a+3b=4c when M is a trivalent metal cation, and a, b, and c are natural numbers.

The invention relates to an optoelectronic material comprising a compound, wherein the compound comprises: (i) one or more cations, A; (ii) one or more first B cations, B.sup.n+; (iii) one or more second B cations, B.sup.m+; and (iv) one or more chalcogen anions, X; wherein the one or more first B cations, B.sup.n+ are different from the one or more second B cations, B.sup.m+; n represents the oxidation state of the first B cation and is a positive integer of from 1 to 7 inclusive; m represents the oxidation state of the second B cation and is a positive integer of from 1 to 7 inclusive; and n+m is equal to 8.