New Dion−Jacobson (n = 3) layered perovskites, A′Cd 2 Nb 3 O 10 (A′ = Rb, Cs), have been synthesized by a solid-state method. Powder X-ray diffraction measurements confirm the noncentrosymmetric orthorhombic (space group Ima2) structures for both rubidium-and cesium-containing layered oxides. The distorted octahedral coordination of the d 0 metal cations (Nb 5+ ) coupled with the increased covalency in the lattice by the introduction of d 10 metal cations (Cd 2+ ) is responsible for the acentric structures. The resulting second-harmonicgeneration (SHG) efficiencies of the polycrystalline samples (size 45−63 μm) using 1064 nm radiation reveal comparable values for CsCd 2 Nb 3 O 10 and nearly 5 times higher output values for RbCd 2 Nb 3 O 10 with respect to potassium dihydrogen phosphate. These structures were further confirmed from transmission electron microscopy and Raman spectroscopy measurements. The optical characteristics show interesting variations to the expected photocatalytic activities. Ion-exchange reactions result in the synthesis of proton-and lithium-containing oxides, which are otherwise inaccessible by direct solid-state reactions. The mobilities of the interlayer ions have also been confirmed by ionic conductivity measurements.

Photogenerated charge separation is a crucial factor determining the enhancement in the energy efficiency of photocatalysts. In this work, through computational simulations of Cu2O crystals with different facets, edge-truncated cubic Cu2O was confirmed to enable efficient charge separation. To verify the computational predictions, Cu2O photocatalysts with two different morphologies and facet orientations, i.e., cubic and edge-truncated cubic structures, were synthesized and characterized. The photocatalytic activity toward the selective reduction of CO2 to methanol on the edge-truncated cubic Cu2O with anisotropic {100} and {110} facets was found to be nearly 5.5-fold higher than that of cubic Cu2O with only {100} facets. This observed difference is ascribed to the effective separation and migration of photogenerated charge carriers as well as the selective accumulation of electrons and holes on different facets of edge-truncated cubic Cu2O crystals. The effects of work function differences between {110} and {100} facets on the electronic band structure and anisotropic charge separation were also identified. These findings provide important guidelines for the design and synthesis of highly efficient and well-defined photocatalysts for CO2 conversion to fuel.

Beyerite, CaBi2O2(CO3)2, is hydrothermally synthesized from Bi(NO3)3 dissolved in ethylene glycol, CaCO3, and Na2CO3 (autoclave, H2O, 140 °C, 72 h).

Realizing the advantages of atomic level mixing, high homogeneity precise stoichiometric control and low processing temperatures, co‐precipitation route employing the polyamine carboxylate, ethylenediamine tetra acetic acid (EDTA) has been followed to determine the extent of dissolution of bismuth in ThO2 adopting fluorite structure. While the precursors containing varying amounts of Th4+ and Bi3+ were X‐ray amorphous, calcining them at 800 °C for 6 h yielded crystalline oxides with fluorite structure till Th0.40Bi0.60O2‐δ. This was supported by Raman spectral measurements in which defect band due to oxygen vacancies was present at around 590 cm−1 in addition to the band due to fluorite at around 460 cm−1. An increasing trend of cubic lattice constant with progressive substitution of bismuth in ThO2 was observed. The direct band gap was found to decrease with increase in bismuth content and was lying in the range of 2.54‐3.62 eV. Porous morphology of the samples was evident in their scanning electron microscopic images and they were macro porous as determined from surface area analysis measurements. Th0.50Bi0.50O2‐δ was found to efficiently catalyze the reduction of some nitroaromatics for nearly six cycles.

Monoclinic [LiAl2(OH)6]OH·2H2O was formed by the hydrolysis of LiAlH4 within few minutes of irradiation with microwaves as confirmed by powder X‐ray diffraction (PXRD), infrared, Raman, 27Al NMR spectroscopic, and thermal analysis experiments. The flaky morphology of crystallites was evident in microscopy images. The compound is mesoporous with surface area of 50 m2/g. When required amounts of corresponding mineral acids were added during the hydrolysis of LiAlH4, exchange of the interlayer hydroxide ion with nitrate and chloride ions was successful. This was verified by the hexagonal symmetry observed in the PXRD patterns together with the evidence gathered from infrared, 27Al NMR spectra, thermal analyses, and the substantial changes in ligand to metal charge‐transfer bands in their UV/Visible spectra. A host of Li‐Al LDH compounds intercalated with aliphatic dicarboxylate (oxalic, malonic, succinic, glutaric, adipic, and sebacic acid) anions were rapidly produced when a mixture of LiAlH4 and the respective acid was irradiated with microwaves for a few minutes. The basal spacing of the dicarboxylate anion intercalated systems increased linearly with the increase in the number of –CH2‐ groups in them. Microwave assisted reaction of ethylene glycol with [LiAl2(OH)6]OH·2H2O resulted in its intercalation.

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