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La0.67Ca0.33-xSrxMnO3 (x = 0.33; 0.03; 0) (LCSM) perovskite magnetocaloric ceramics were prepared by solid state synthesis in air and sintering at 1520°C. The phase composition was checked by x-ray powder diffraction. Microstructure analyses were done by scanning electron microscopy. The influence of high pressure oxygenation on magnetisation behaviour is shown. [ABSTRACT FROM AUTHOR]

The title compound is prepared by solid state reaction from mixtures of PbO, PbO2, Fe2O3, and OsO3 in the ratio of 3:1:1:2 (Pt capsule, 8 GPa, 1673 K, 30 min). [ABSTRACT FROM AUTHOR]

The lead-free perovskite (1-x)Bi(Zn0.5Ti0.5)O3-xBiFeO3 (x = 0.1-0.6) is synthesized from stoichiometric mixtures of Bi2O3, ZnO, TiO2, and Fe2O3 (Au capsule, 6 GPa, 1373 K, 30 min, annealing at 673 K for 1 h). [ABSTRACT FROM AUTHOR]

Review: 44 refs. [ABSTRACT FROM AUTHOR]

Proton trapping is a major cause of retardation of proton conduction in the bulk of perovskite oxides and results from the strong electrostatic attraction between positively charged protons and negatively charged acceptors. In their Communication on page 13499 ff., S.‐Y. Chung and co‐workers show that clustering of oxygen vacancies to acceptors can be induced by post‐annealing and that proton trapping is thereby suppressed. The impact of the oxygen vacancies and their effective charge on ionic conduction is shown. [ABSTRACT FROM AUTHOR]

Highly luminescent CsPb2Br5 nanoplatelets are prepared by a scalable precipitation reaction from mixtures of PbBr2, CsBr, hexylammonium bromide, DMF, and toluene (yield given in g). [ABSTRACT FROM AUTHOR]

The title compound is synthesized by solid state reaction of La2O3, SrCO3, K2CO3, and MnO2 (calcination at 900-1100 °C, sintering at 1200 °C for 24 h). [ABSTRACT FROM AUTHOR]

Polycrystalline Ba14Mn1.75Ta10.5O42 (BMT) is prepared by calcination of a stoichiometric mixture of BaCO3, MnCO3, and Ta2O5 (Al2O3 crucible, 1473 K, 8 h), pelletizing, and further firing in air (1773 K, 12-24 h). [ABSTRACT FROM AUTHOR]

Crystals of the anti-Perovskites (III), (V), (VIII), (IX), and (X) are hydrothermally prepared with yields greater than 90% and characterized by single crystal XRD, UV/VIS spectroscopy, and magnetic measurements. [ABSTRACT FROM AUTHOR]

Phosphor with extremely narrow emission line widths, high brightness, and wide color emission tunability in visible regions is required for display and lighting applications, yet none has been reported in the literature so far. In the present study, single-sized lead halide perovskite (APbX3; A = CH3NH3 and Cs; X = Cl, Br, and I) nanocrystalline (NC) phosphors were achieved for the first time in a one-pot reaction at room temperature (25 °C). The size-dependent samples, which included four families of CsPbBr3 NCs and exhibited sharp excitonic absorption peaks and pure band gap emission, were directly obtained by simply varying the concentration of ligands. The continuity of the optical spectrum can be successively tuned over the entire UV–visible spectral region (360–610 nm) by preparing CsPbCl3, CsPbI3, and CsPb(Y/Br)3 (Y = Cl and I) NCs with the use of CsPbBr3 NCs as templates by anion exchange while maintaining the size of NCs and high quantum yields of up to 80%. Notably, an emission line width of 10–24 nm, which is completely consistent with that of their single particles, indicates the formation of single-sized NCs. The versatility of the synthetic strategy was validated by extending it to the synthesis of single-sized CH3NH3PbX3 NCs by simply replacing the cesium precursor by the CH3NH3X precursor. [ABSTRACT FROM AUTHOR]

Polycrystalline La0.3Sm0.2Sr0.5Ti0.5 Fe0.5O3 is prepared by a citrate-gel reaction starting with stoichiometric amounts of La2O3, Sm2O3, SrCO3, Ti(O-iPr)4, and Fe(NO3)3 in aq. [ABSTRACT FROM AUTHOR]

Polycrystalline Mn2MnReO6 is prepared by hot press sintering of stoichiometric mixtures of MnO and ReO3 (Pt capsule in multianvil press, 1673 K, 5 GPa, 1 h; decompression over 8-12 h). [ABSTRACT FROM AUTHOR]

The title material is prepared by solid state reaction of a stoichiometric mixture of Bi2O3, BiOCl, and Nb2O5 (evacuated silica tube, 1173 K, 20 h) and characterized by powder XRD and UV/VIS diffuse reflectance spectroscopy. [ABSTRACT FROM AUTHOR]

Perovskite oxides M1M2O3 (M1: Ca, Sr, Ba; M2: Ti, Zr, Hf) are prepared by low-temperature solid state reaction of M1(OH)2 powders with M2O2·nH2O gels. [ABSTRACT FROM AUTHOR]

We present here solution-processed photodetectors based on a methyl ammonium lead iodide perovskite (MAPbI3) and nanocrystalline graphite (NCG) hybrid composite. The highest responsivity of the best MAPbI3/NCG photodetector was 795 mA W−1 at 500 nm visible light, which is almost twice as high as that of the NCG-free MAPbI3 photodetector (408 mA W−1). The enhanced performance of the MAPbI3/NCG photodetector arises from the improved charge extraction at the MAPbI3/NCG interface. The dependence of photodetector performance on the mass percentage of NCG (the ratio of NCG to MAPbI3) in the hybrid materials is also reported here, and is correlated to the fabrication process. Moreover, by comparing the responsivity of the devices with different channel lengths, we show that the performance of hybrid photodetectors can be further tuned by tailoring the channel length. [ABSTRACT FROM AUTHOR]

Sr2MnO3F is prepared by hot pressing and annealing of stoichiometric amounts of SrF2, SrO, and Mn2O3 (Pt capsule in belt-type high-pressure cell, 6 GPa, 1800 °C, 45 min). [ABSTRACT FROM AUTHOR]

The manipulation of material properties in perovskite oxide heterojunctions has been increasingly studied, owing to their interacting lattice, charge, spin and orbital degrees of freedom. In this work, the switching, ferroelectricity and magneto-transport properties of epitaxially grown perovskite Pb(Zr0.52Ti0.48)O3 layers sandwiched between Fe3O4 (top electrode) and SrRuO3 (bottom electrode) are investigated. These films show a typical ferroelectric polarization of ∼50 μC/cm2. Once the Pb(Zr0.52Ti0.48)O3 films become thinner (∼30 nm), one can set (reset) the Fe3O4/Pb(Zr0.52Ti0.48)O3/SrRuO3 structures into a low (high) resistance state via formation (rupture) of an Fe-related filament in Pb(Zr0.52Ti0.48)O3 through manipulation of an electric field. Interestingly, at the low-resistance state, a prominent magnetoresistance signal of ∼3% was observed. There is no magnetoresistance signal detected in the virgin Pb(Zr0.52Ti0.48)O3 film (before switching), high-resistive state Pb(Zr0.52Ti0.48)O3 film and Au/Pb(Zr0.52Ti0.48)O3/SrRuO3. These phenomena are attributed to the diffusion of Fe-related ions into the Pb(Zr0.52Ti0.48)O3 film, turning a non-magnetic and insulating layer of perovskite Pb(Zr0.52Ti0.48)O3 into a magnetic and semiconducting-like Pb(Zr0.52Ti0.48)O3. The magneto-transport properties of Fe3O4/Pb(Zr0.52Ti0.48)O3/SrRuO3 have been studied extensively. Such resistance–ferroelectric–ferromagnetic coupling in a single compound paves the way to the realization of a non-volatile multiple-state Pb(ZrTi)O3 hybrid memory, as well as new computing approaches. [ABSTRACT FROM AUTHOR]

This work aims to simplify multi-dimensional femtosecond transient absorption microscopy (TAM) data into decay associated amplitude maps (DAAMs) that describe the spatial distributions of dynamical processes occurring on various characteristic timescales. Application of this method to TAM data obtained from a model methyl-ammonium lead iodide (CH3NH3PbI3) perovskite thin film allows us to simplify the data set comprising 68 time-resolved images into four DAAMs. These maps offer a simple means to visualize the complex electronic excited-state dynamics in this system by separating distinct dynamical processes evolving on characteristic timescales into individual spatial images. This approach provides new insight into subtle aspects of ultrafast relaxation dynamics associated with excitons and charge carriers in the perovskite thin film, which have recently been found to coexist at spatially distinct locations. [ABSTRACT FROM AUTHOR]

Correction for ‘Synthesis and crystal structure of a new hexagonal perovskite 7H-Ba7Li1.75Mn3.5O15.75 with Mn4+/Mn5+ charge distribution’ by N. V. Tarakina et al., Dalton Trans., 2015, DOI: 10.1039/c5dt01528f. [ABSTRACT FROM AUTHOR]

Perovskite/c-Si tandem solar cells (TSCs) have become a promising candidate in recent years for achieving efficiency over 30%. Although general analysis has shown very high upper limits for such TSCs, it remains largely unclear what specific optical structures could best approach these limits. Here we propose the combination of perovskite/c-Si tandem structure with inverted nanopyramid morphology as a practical way of achieving efficiency above 31% based on realistic solar cell parameters. By full-field simulation, we have shown that an ultra-low surface reflectance can be achieved by tuning the pyramid geometry within the range of experimental feasibility. More importantly, we have demonstrated that the index-guided modes can be excited within the top cell layer by introducing a TCO interlayer that prevents coupling of guided light energy into the bottom cell. This light trapping scheme has shown superior performance over the Bragg stack intermediate reflector utilized in previous micropyramid-based TSCs. Finally, by controlling the coupling between the top and bottom cell through the thickness of the interlayer, current generation within the tandem can be optimized for both two- and four-terminal configurations, yielding efficiencies of 31.9% and 32.0%, respectively. These results have provided useful guidelines for the fabrication of perovskite/c-Si TSCs. [ABSTRACT FROM AUTHOR]

Review: such as H2 production and pollutant degradation; 133 refs. [ABSTRACT FROM AUTHOR]

Review: 42 refs. [ABSTRACT FROM AUTHOR]

A correction to the article "Pseudohalide-Induced Moisture-Tolerance in Perovskite CH3NH3Pb(SCN)2I Thin Films" that was published in the 2015 issue is presented.

Na0.5Bi0.5(Ti0.98Mn0.02)O3(NBTMn) thin film was fabricated on fluorine-doped tin oxide (FTO)/glass substrate via a chemical solution decomposition method. The microstructure and electrical performances of NBTMn thin film were investigated. The XRD pattern reveals that the NBTMn thin film is crystallised into a phase-pure polycrystalline perovskite structure. Also the film possesses a homogeneous structure. Enhanced ferroelectricity is obtained with a large remnant polarisation (Pr) of 19.8 μC/cm2reflected by polarisation–electric field (P–E) hysteresis loop, which is consistent with the typical butterfly-shaped capacitance–voltage (C–V) curve. At the optimum applied voltage of ±22 V, a maximum value of 27% for dielectric tunability is obtained. Additionally, the NBTMn thin film shows a dielectric constant of 422, dissipation factor of 0.06 and figure of merit of 4.5 at 100 kHz. [ABSTRACT FROM AUTHOR]

Abstract: The crystal structure of a natural specimen of Tetrawickmanite (Langban, Sweden) with the ideal composition of Mn2+Sn4+(OH)6 (tetragonal space group P42/n, Z = 4, single crystal XRD) belongs to the octahedral‐framework group of hydroxide‐perovskite minerals described by the general formula BB′(OH)6. [ABSTRACT FROM AUTHOR]

LaTiO3-δ and La0.8A0.2TiO3-δ (A: Ba, Sr, Ca) are prepared by sol-gel processing of La(NO3)3, alkali acetates, and (Pr-O)4Ti using citric acid and PEG (60 °C, 8 h). [ABSTRACT FROM AUTHOR]

The article discusses a study within the issue by Pitcher et al. showing how layered perovskite materials that are both electrically polar and weakly ferromagnetic at temperatures up to 330 K (kelvin) can be designed with the right chemical substitutions.

Double perovskite oxide Sr2CoFeO6 (SCFO) has been obtained using a high-pressure and high-temperature (HPHT) synthesis method. Valence states of Fe and Co and their distributions in SCFO were examined with X-ray photoelectron spectroscopy. The electric transport behavior of SCFO showed a semiconductor behavior that can be well described by Mott’s law for variable-range hopping conduction. The structural stability of SCFO was investigated at pressures up to 31 GPa with no pressure-induced phase transition found. Bulk modulus B0 was determined to be 163(2) GPa by fitting the pressure–volume data to the Birch–Murnaghan equation of state. [ABSTRACT FROM AUTHOR]

Ni0.2Sr0.8ZrO3 catalyst is hydrothermally prepared from a stoichiometric mixture of ZrOCl2, Sr(NO3)2, and Ni(NO3)2 (autoclave, 180 °C, 72 h). [ABSTRACT FROM AUTHOR]

Polycrystalline LnPbMgSbO6 (Ln: La, Pr, Nd) are prepared by a two-step method. [ABSTRACT FROM AUTHOR]

The title compound is prepared by solid state reaction of a stoichiometric mixture of MoO3, SrCO3, and Sc2O3. [ABSTRACT FROM AUTHOR]

Review: 44 refs. [ABSTRACT FROM AUTHOR]

Scandium perovskite (Sc0.94Mn0.06)Mn0.65Ni0.35O3, synthesized at high pressure and high temperature, has a triclinic structure (space group ) at room temperature and ambient pressure with a √2apx√2apx2ap structure with α≈90°, β≈89°, γ≈90°. Magnetic measurements show that the material displays Curie-Weiss behaviour above 50 K with C=2.11 emu K mol-1 (μeff=4.11 μB per formula unit) and θ=−95.27 K. Bond valence sum analysis of the crystal structure shows that manganese is present in three different oxidation states (+2, +3, +4), with the +2 oxidation state on the A site resulting in a highly tilted perovskite structure (average tilt 21.2° compared with 15.7° calculated for LaCaMnNbO6), giving the formula. [ABSTRACT FROM AUTHOR]

CaOsO3 and SrOsO3 are synthesized by high-pressure solid state reactions of CaO or SrO and OsO2 (Pt capsule, 6 GPa, 1500-1700 °C, 1 h). [ABSTRACT FROM AUTHOR]

CsTlCl3 (I) is prepared via the precursor Cs2TlCl5·H2O (II) which is obtained by precipitation from a HCl solution of CsCl and Tl2O3 using H2O. [ABSTRACT FROM AUTHOR]

The title compounds are prepared from stoichiometric mixtures of In2O3 or Sc2O3 and Rh2O3 (Au capsules, 6 GPa, 1500 K, 2 h). [ABSTRACT FROM AUTHOR]

The new title perovskite is synthesized from mixtures of Ca(VO3)2, Co(VO3)2, and Co (14-18 GPa, 900-1300 °C, 0.5-8 h). [ABSTRACT FROM AUTHOR]

The title compounds are prepared from mixtures of MF2 (M: Ca, Sr, Ba) and NaI (Pt crucible, 650 °C, 18 h, yield given in g). [ABSTRACT FROM AUTHOR]