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Acetamidinium bromoplumbate, denoted (ACA)PbBr3, was synthesized from acetamidinium bromide and lead bromide in liquid medium under ambient atmosphere. The large radius of the acetamidinium group of (ACA)PbBr3 accommodates the 4H BaRuO3 structure, which has a hexagonal array of infinite face‐shared and corner‐shared [PbBr6]4− units. (ACA)PbBr3 was characterized by single X‐ray diffraction, chemical analyses, thermal analyses, 1H NMR, and FT‐IR spectroscopy. [ABSTRACT FROM AUTHOR]

Silicon oxide‐coated lithium aluminum layered double hydroxide (LixAl2‐LDH@SiO2) nanocrystals (NCs) are investigated to selectively separate lithium cations in aqueous lithium resources. We directly synthesized LixAl2‐LDH NC arrays by oxidation of aluminum foil substrate under a urea and lithium solution. Various lithium salts, including Cl−, CO32−, NO3−, and SO42−, were applied in aqueous solution to confirm the anion effect on the captured and released lithium quantity of the LixAl2‐LDH NCs. In a 5% solution of sulfate ions mix with lithium chloride, the LixAl2‐LDH NCs separated a larger quantity of lithium than in other anion conditions. To enhance regeneration stability and lithium selectivity, thin layers of SiO2 were coated onto the LixAl2‐LDH nanostructure arrays for inhibition of nanostructure destruction after desorption of lithium cations in hot water. The LixAl2‐LDH@SiO2 nanostructures showed enhanced properties for lithium adsorption, including increase of stable regeneration cycles from three to five cycles, and they showed high lithium selectivity in the Mg2+, Na+, and K+ cation mixed aqueous resource. Our nanostructured LDH lithium adsorbents would provide a facile and efficient application for cost‐efficient and large‐scale lithium production. [ABSTRACT FROM AUTHOR]

The direct synthesis of nanostructured electrode materials on three‐dimensional substrates is important for their practical application in electrochemical cells without requiring the use of organic additives or binders. In this study, we present a simple two‐step process to synthesize a stable core–shell structured cobalt sulfide/cobalt aluminum hydroxide nanosheet (LDH‐S) for pseudocapacitor electrode application. The cobalt aluminum layered double hydroxide (CoAl‐LDH) nanoplates were synthesized in basic aqueous solution with a kinetically‐controlled thickness. Owing to the facile diffusion of electrolytes through the nanoplates, thin CoAl‐LDH nanoplates have higher specific capacitance values than thick nanoplates. The as‐grown CoAl‐LDH nanoplates were transformed into core–shell structured LDH‐S nanosheets by a surface modification process in Na2S aqueous solution. The chemically robust cobalt sulfide (CoS) shell increased the electrochemical stability compared to the sulfide‐free CoAl‐LDH electrodes. The LDH‐S electrodes exhibited high electrochemical performance in terms of specific capacitance and rate capability with a galvanostatic discharge of 1503 F g−1 at a current density of 2 A g−1 and a specific capacitance of 91 % at 50 A g−1. Pseudocapacitor without sacrificing power capability: Core‐shell structured cobalt sulfide/cobalt aluminum layered double hydroxide electrodes were developed for pseudocapacitors via a direct synthesis process on 3D metal substrates. Sulfide modification is a facile and efficient way to enhance the electrical performance and stability of 3D nanostructured electrode materials. The specific capacitance of the modified electrode was more than 91 % of its initial capacitance, with discharge current densities ranging from 2 to 50 A g−1. [ABSTRACT FROM AUTHOR]

CuInS2 semiconductor was synthesized from CuIn(OH)5 precursors via facile anion exchange in aqueous Na2S solution at room temperature. CuIn(OH)5 was prepared from copper and indium salts and NaOH by co-precipitation in aqueous solution as a polycrystalline. The sulfide exchange reaction did not alter the copper to indium ratio. The reaction resulted in stoichiometric amounts of sulfur in the CuInS2 sample at room temperature. Fourier transform infrared spectra and ion chromatography were used to analyze the impurities, including chloride and nitrate in the prepared samples. CuInS2 showed a chalcopyrite crystal structure after annealing at 500°C under 4% hydrogen-mixed argon atmosphere. The bandgap of the CuInS2 thin film device was estimated to be 1.46 eV. [ABSTRACT FROM AUTHOR]