Alloy negative electrodes for Li-ion batteries.

Despite the impressive photovoltaic performances with power conversion efficiency beyond 22%, perovskite solar cells are poorly stable under operation, failing by far the market requirements. Various technological approaches have been proposed to overcome the instability problem, which, while delivering appreciable incremental improvements, are still far from a market-proof solution. Here we show one-year stable perovskite devices by engineering an ultra-stable 2D/3D (HOOC(CH2)4NH3)2PbI4/CH3NH3PbI3 perovskite junction. The 2D/3D forms an exceptional gradually-organized multi-dimensional interface that yields up to 12.9% efficiency in a carbon-based architecture, and 14.6% in standard mesoporous solar cells. To demonstrate the up-scale potential of our technology, we fabricate 10 × 10 cm2 solar modules by a fully printable industrial-scale process, delivering 11.2% efficiency stable for >10,000 h with zero loss in performances measured under controlled standard conditions. This innovative stable and low-cost architecture will enable the timely commercialization of perovskite solar cells. Up-scaling represents a key challenge for photovoltaics based on metal halide perovskites. Using a composite of 2D and 3D perovskites in combination with a printable carbon black/graphite counter electrode; Granciniet al., report 11.2% efficient modules stable over 10,000 hours.

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One-Year stable perovskite solar cells by 2D/3D interface engineering

Research to develop alternative electrode materials with high energy densities in Li-ion batteries has been actively pursued to satisfy the power demands for electronic devices and hybrid electric vehicles. This critical review focuses on anode materials composed of Group IV and V elements with their composites including Ag and Mg metals as well as transition metal oxides which have been intensively investigated. This critical review is devoted mainly to their electrochemical performances and reaction mechanisms (313 references).

Li-alloy based anode materials for Li secondary batteries.

Polyoxometalates (POMs) are discrete anionic metaloxygen clusters which can be regarded as soluble oxide fragments. They exhibit a great diversity of sizes, nuclearities, and shapes. They are built from the connection of {MOx} polyhedra, M being a d-block element in high oxidation state, usually VIV,V, MoVI, or WVI.1 While these species have been known for almost two centuries, they still attract much interest partly based on their large domains of applications. They play a great role in various areas ranging from catalysis,2 medicine,3 electrochemistry,4 photochromism,5 to magnetism.6 This palette of applications is intrinsically due to the combination of their added value properties (redox properties, large sizes, high negative charges, nucleophilicity...). Parallel to this domain, the organic-inorganic hybrids area has followed a similar expansion during the last 10 years. The concept of organic-inorganic hybrid materials * To whom correspondence should be addressed. E-mail: dolbecq@ chimie.uvsq.fr. Chem. Rev. 2010, 110, 6009–6048 6009

Hybrid Organic−Inorganic Polyoxometalate Compounds: From Structural Diversity to Applications

The hybrid two-dimensional (2D) halide perovskites have recently drawn significant interest because they can serve as excellent photoabsorbers in perovskite solar cells. Here we present the large scale synthesis, crystal structure, and optical characterization of the 2D (CH3(CH2)3NH3)2(CH3NH3)n−1PbnI3n+1 (n = 1, 2, 3, 4, ∞) perovskites, a family of layered compounds with tunable semiconductor characteristics. These materials consist of well-defined inorganic perovskite layers intercalated with bulky butylammonium cations that act as spacers between these fragments, adopting the crystal structure of the Ruddlesden–Popper type. We find that the perovskite thickness (n) can be synthetically controlled by adjusting the ratio between the spacer cation and the small organic cation, thus allowing the isolation of compounds in pure form and large scale. The orthorhombic crystal structures of (CH3(CH2)3NH3)2(CH3NH3)Pb2I7 (n = 2, Cc2m; a = 8.9470(4), b = 39.347(2) A, c = 8.8589(6)), (CH3(CH2)3NH3)2(CH3NH3)2Pb3I10 (...

http://pubs.acs.org/doi/pdf/10.1021/acs.chemmater.6b00847

Ruddlesden-Popper Hybrid Lead Iodide Perovskite 2D Homologous Semiconductors

Three new transition metal copper(II) selenites or tellurites, namely, CdCu(SeO3)2 (1), HgCu(SeO3)2 (2), and Hg2Cu3(Te3O8)2 (3), have been obtained by conventional hydrothermal reactions of CdO (or Hg2Cl2), CuO and SeO2 (or TeO2). Compounds 1 and 2 are isostructural and crystallize in P21/c. Their structures feature a 3D anionic framework of Cu(SeO3)22− with 1D channels of eight-membered rings (MRs) along the c-axis and a-axis, respectively, which are filled by Cd2+ or Hg2+ cations. Compound 3 crystallizes in a tetragonal system of space group P4212. Its structure is characterized by a [Cu3(Te3O8)2]2− honeycomb layer composed of [Te3O8]4− anions interconnected by Cu2+ ions with 1D channels of 8-MRs along the c-axis. TOPOS analysis indicates that the copper(II) tellurite layer exhibits a new topological structure with a Schlafli symbol of {46·89}2{46}3. The above anionic copper(II) tellurite layers are further linked by dumbbell Hg22+ cations to form a novel 3D framework. Magnetic measurements based on magnetic susceptibility and heat capacity indicate that compounds 1 and 2 show a spin-singlet ground state with a spin gap based on the [Cu2O8]12− dimeric model, whereas compound 3 exhibits a 2D spin-system with an antiferromagnetic ordering around 25 K correlated with its honeycomb [Cu3(Te3O8)2]2− layer. Furthermore, crystalline structures, thermal stabilities, IR spectra and UV-Vis diffuse reflectance spectra have also been studied.

Structural and magnetic studies on three new mixed metal copper(II) selenites and tellurites.

A new Er(III)–Na(I) coordination polymer of stoichiometry [NaEr2L5(H2O)6(NO3)](NO3)·3.5H2O (HL = picolinic acid N-oxide) has been synthesized and characterized by single-crystal X-ray analysis. Crystals are triclinic, PĪ with a = 9.823(2), b = 12.453(2), c = 20.643(4) A; α = 98.49(3), (β = 101.40(3), γ = 108.69(3)°; V = 2284(1) A3; Z = 2. Of the two independent eight-coordinate erbium(III) ions in this complex, one is surrounded by four bidentate chelating L ligands, and the other by one bidentate chelating L ligand, four aqua ligands and two anti-carboxylate oxygen atoms from two neighboring [ErL4] units. The sodium(I) ion is in a distorted octahedral environment, being coordinated by a unidentate nitrate anion, three aqua ligands and two anti-carboxylate oxygen atoms from two adjacent [ErL4] units. The complex is built from zigzag chains of syn-anti carboxylate-bridged erbium(III) moieties directed in the a direction, which are cross-linked pairwise by aqua-bridgeddimericsodium(I) units. The resulting composite polymeric chains are further connected by hydrogen bonds to form a three-dimensional network.

Synthesis and crystal structure of a polymeric erbium(III)-sodium(I) coordination complex of picolinic acid N-oxide

Birefringent materials capable of modulating the polarization of light have attracted intensive studies because of their wide utilization in optical communication and the laser industry. Herein, two new lead(II)-based cyanurates, namely, Pb(H2C3N3O3)X (X = OH, F), were synthesized by hydrothermal methods, and the first halogen-containing metal cyanurate Pb(H2C3N3O3)F was successfully obtained by the rational substitution of a homovalent anion. Pb(H2C3N3O3)X (X = OH, F) belong to space group P1̅, and their structures display a neutral [Pb(H2C3N3O3)X] (X = OH, F) layer. The Pb2+ ions in Pb(H2C3N3O3)(OH) are interconnected by hydroxyl groups and oxygen atoms of cyanurate anions into a 1D [PbO(OH)]- chain, whereas the Pb2+ ions in Pb(H2C3N3O3)F are interconnected by F- anions and oxygen atoms of cyanurate anions into a 2D [PbOF]- layer. The π-π interactions between adjacent hydroisocyanurate rings and the hydrogen bonds between neighboring neutral layers provide additional stability to the structures. Luminescent studies show that Pb(H2C3N3O3)(OH) and Pb(H2C3N3O3)F emit yellow-green and blue light, respectively. Theoretical calculations unveiled their birefringences of 0.079 and 0.203@1064 nm and their band gaps of 3.96 and 4.96 eV, respectively, for OH- and F- containing materials. Obviously, the substitution of OH- by F- with the largest electronegativity can simultaneously improve both the birefringence and band gap.

From Pb(H2C3N3O3)(OH) to Pb(H2C3N3O3)F: Homovalent Anion Substitution-Induced Band Gap Enlargement and Birefringence Enhancement.

Synthesis and crystal structure of La4S3Si2O7

https://www.onlinelibrary.wiley.com/doi/pdf/10.1002/ange.201702499

Jiang-Gao Mao

Papers

Structural and magnetic studies on three new mixed metal copper(II) selenites and tellurites.

Synthesis and crystal structure of a polymeric erbium(III)-sodium(I) coordination complex of picolinic acid N-oxide

From Pb(H2C3N3O3)(OH) to Pb(H2C3N3O3)F: Homovalent Anion Substitution-Induced Band Gap Enlargement and Birefringence Enhancement.

Synthesis and crystal structure of La4S3Si2O7

Corrigendum: Bi(IO3 )F2 : The First Metal Iodate Fluoride with a Very Strong Second Harmonic Generation Effect.