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The efficiency and reproducibility of perovskite solar cells (PSCs) are significantly influenced by the purity of lead iodide (PbI2) in the raw materials used. Pb(OH)I has been identified as the primary impurity generated from PbI2 in water-based synthesis. Consequently, a comprehensive investigation into the impact of Pb(OH)I impurities on film and device performance is essential. In this study, PbI2, with varying stoichiometries, was synthesized to examine the effects of different Pb(OH)I levels on perovskite device performance. The characterization results revealed that even trace amounts of Pb(OH)I impede the formation of precursor prenucleation clusters. These impurities also increase the energy barrier of the α-phase and facilitate the transition of the intermediate phase to the δ-phase. These effects result in poor perovskite film morphology and sub-optimal photovoltaic device performance. To address these issues, a cost-effective method for preparing high-stoichiometry PbI2 was developed. The formation of Pb(OH)I was effectively inhibited through several strategies: adjusting solution pH and temperature, modifying material addition order, simplifying the precipitation–recrystallization process, and introducing H3PO2 as an additive. These modifications enabled the one-step synthesis of high-purity PbI2. PSCs prepared using this newly synthesized high-stoichiometry PbI2 demonstrated photovoltaic performance comparable to those fabricated with commercial PbI2 (purity ≥ 99.999%). Our novel method offers a cost-effective alternative for synthesizing high-stoichiometry PbI2, thereby providing a viable option for the production of high-performance PSCs. [ABSTRACT FROM AUTHOR]

In the study conducted it shows that, at room temperature extending further into the nanometer regime to produce catalytically active TiO (sub 2-x) N (sub x) nanoparticles that absorb well into the visible and near-infrared region. Speculate that this effect may lead to the significant reduction in nitrogen uptake and photocatalytic activity for the acetate-treated samples relative to TiO (sub 2-x) N (sub x) and the corresponding chloride and nitrate-treated samples.

Bimetal oxides NiO/NiCo2O4 were successfully fabricated by using metal-organic frameworks (MOFs) as the precursor. The prepared NiO/NiCo2O4 showed hollow sphere and rod-like structures, respectively. When evaluated as an anode material for lithium-ion battery, a sphere-like NiO/NiCo2O4 showed an initial discharge capacity of 1778 mAh/g and reversible capacity of 920 mAh/g at 100 mA/g after 100 cycles. And a rod-like NiO/NiCo2O4 displayed initial discharge capacity of 1800 mAh/g and stabilized at an average capacity of 1198 mAh/g after 100 cycles. The results showed that the materials with the rod-like structure were much more stable and had better rate capability and more superior cyclic stability. The rod-like structure had a shorter transmission distance of Li+, which could maintain its stable rod-like structure in the long-term cycle. This strategy could shed light on designing stable electrode materials for conversion devices and energy storages. [ABSTRACT FROM AUTHOR]

In this work, the pseudohalide thiocyanate has been demonstrated as a promising alternative to the halide anion to engineer optoelectronic properties of inorganic/organic hybrid perovskites because it exhibits better chemical stability than the halide anion. Previous reports have suggested that the ionic radii and electronegativity of SCN− is close to that of I−; the SCN− doped CH3NH3PbI3 exhibited similar optical properties as pure CH3NH3PbI3. Consequently, it was expected that doping of CsPbBr3 perovskite with SCN− would result in band gap narrowing. Interestingly, the photoluminescent all-inorganic CsPbBr3 perovskite nanocrystals exhibit an abnormal blue shift in optical properties and improvement of the crystallinity when successfully doped by SCN−. Combined experimental and theoretical investigations revealed that doping of the CsPbBr3 perovskite with the rod-like SCN− anion introduced disorder in the crystal lattice, leading to its expansion, and impacted the electronic structure of the perovskite with band gap broadening. [ABSTRACT FROM AUTHOR]

In the title mol-ecule, C(13)H(16)O(6), the cyclo-hexa-1,4-diene ring adopts a flat boat conformation (r.m.s. deviation from planarity = 0.060 Å) and the five-membered tetra-hydro-furan ring adopts an envelope conformation with the carboxyl group-substituted C atom as the flap. The dihedral angle at the spiro junction is 89.1 (1)°. In the crystal, mol-ecules are linked through weak C-H⋯O and van der Waals inter-actions.

In the title compound, C(38)H(38)Br(2)N(4)O(4)S(2), there is a crystallographic inversion center located at the mid-point of the alkene bond. The dihedral angle between the aromatic ring systems in the asymmetric unit is 87.69 (19)°. In the crystal, adjacent mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, generating R(2) (2)(16) loops within [1[Formula: see text]0] chains. Short Br⋯Br contacts [3.6148 (9) Å] are observed between adjacent mol-ecules.