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

The first bismuth selenite fluoride, BiFSeO3, was obtained by aliovalent substitution of 2D BiOIO3. Its structure features a 3D network composed of 1D [BiF]2+ chains interconnected by SeO3 groups. BiFSeO3 exhibits a very strong second harmonic generation (SHG) effect of about 13.5 times that of KH2PO4 (KDP) under 1064 nm laser radiation and 1.1 times that of KTiOPO4 (KTP) under 2.05 μm laser radiation, which is the highest among all of the metal selenites reported. It has also very simple chemical composition and can be synthesized easily under mild hydrothermal conditions.

BiFSeO3: An Excellent SHG Material Designed by Aliovalent Substitution.

Metal selenites and tellurites are a class of very important compounds. In this paper, the structures and properties of metal selenites or tellurites combining with transition-metal (TM) ions with the d0 electronic configuration or tetrahedral MO4 building blocks of post-transition main-group elements were reviewed. Most compounds in the alkali or alkaline-earth−d0 TM−SeIV (or TeIV)−O systems exhibit extended anionic architectures composed of distorted octahedra of (d0) TM cations and tellurite or selenite groups. The distortion of the octahedron is always away from the lone-pair cation, and some of them exhibit excellent second-order nonlinear optical properties due to the adductive effects of two types of bond polarizations. Because of the high coordination number of LnIII ions, most of compounds in the Ln−d0 TM−SeIV (or TeIV)−O systems are not second-harmonic-generation active; however, they are able to emit strong luminescence in the visible or near-IR region; also in most cases, the d0 TM cations are...

Structures and Properties of Functional Metal Selenites and Tellurites

Hydrothermal reactions of transition metal salts with HO2CCH2N(CH2PO3H2)2 (H5L) and 4,4‘-bipyridine (bipy) lead to two new metal carboxylate-diphosphonates, namely, Co3(H2L)2(H2O)4(bipy)2·11H2O (1) with a layered structure, and a blue luminescent compound, Zn5L2(bipy)2·9H2O (2) with a pillared layered structure. In compound 1, three Co(II) ions are interconnected by two chelating and bridging phosphonate ligands to form a trinuclear unit, and such units are further cross-linked via bridging bipy ligands to form a 2D layer. In compound 2, the zinc(II) ions in the trigonal bipyramidal or tetrahedral geometries are interconnected via chelating and bridging carboxylate-phosphonate ligands into 2D layers which are further cross-linked by 4,4‘-bipy ligands into a pillared layered architecture. Results of luminescent studies indicate that compound 2 is a blue light luminescent material.

New Types of Layered and Pillared Layered Metal Carboxylate-Phosphonates Based on the 4,4‘-Bipyridine Ligand

Hydrothermal reactions of lanthanide(III) salts with m-sulfophenylphosphonic acid (H3L1) and 1,10-phenanthroline (phen) or N,N‘-piperazinebis(methylenephosphonic acid) (H4L2) afforded six novel lanthanide(III) sulfonate−phosphonates based on tetranuclear clusters, namely, [La2(L1)2(phen)4(H2O)]·4.5H2O (1), [Ln2(L1)2(phen)2(H2O)5]·3H2O (Ln = Nd, 2; Eu, 3; Er, 4), and [Ln2(HL1)(H2L2)2(H2O)4]·8H2O (Ln = La, 5; Nd, 6). Compounds 2−4 contain discrete tetranuclear lanthanide(III) cluster units in which four lanthanide(III) ions are bridged by two tridentate and two tetradentate phosphonate groups. In compound 1, the tetranuclear clusters are further interconnected into a 1D chain through the coordination of the sulfonate groups. The structures of compounds 5 and 6 can be viewed as a 3D architecture based on a different types of tetranuclear cluster units that are interconnected by bridging H2L2 anions. In the tetranuclear clusters of compounds 5 and 6, the four lanthanide(III) centers are interconnected by only...

Rational design of 0D, 1D, and 3D open frameworks based on tetranuclear lanthanide(III) sulfonate-phosphonate clusters.

Hydrothermal reactions of lanthanide metal salts with MeN(CH(2)CO(2)H)(CH(2)PO(3)H(2)) (H(3)L) and 5-sulfoisophthalic acid monosodium salt (NaH(2)BTS) lead to four isomorphous lanthanide carboxylate-phosphonate-sulfonate hybrids, namely, Ln(H(2)L)(HBTS)(H(2)O)(2).H(2)O (Ln = La (1), Pr (2), Nd (3), Gd (4)). Their structures have been established by X-ray single-crystal diffraction. The interconnection of the lanthanide(III) ions by carboxylate-phosphonate ligands results in a 1D double chain; these double chains are further bridged by bidentate bridging carboxylate-sulfonate ligands to form a layer. The luminescent properties of compounds 3 and 4 have also been studied.

Jiang-Gao Mao

Papers

BiFSeO3: An Excellent SHG Material Designed by Aliovalent Substitution.

Structures and Properties of Functional Metal Selenites and Tellurites

New Types of Layered and Pillared Layered Metal Carboxylate-Phosphonates Based on the 4,4‘-Bipyridine Ligand

Rational design of 0D, 1D, and 3D open frameworks based on tetranuclear lanthanide(III) sulfonate-phosphonate clusters.

Syntheses, crystal structures, and luminescent properties of novel layered lanthanide sulfonate-phosphonates.