Over 10% Efficiency Pure Sulfide Kesterite Solar Cells on Transparent Electrode with Cd-Ag Co-Alloying.

The environmentally friendly elements composed of high bandgap pure sulfide CuZnSnS (CZTS) semiconductor has broad prospects for building integrated photovoltaic, double-sided, and semi-transparent solar cells when fabricated on transparent substrates. The key issues limiting the performance of CZTS solar cells are poor absorber quality and unfavorable band energy alignment causing serious charge carrier recombination. Here, thefabrication of CZTS solar cells are reported on fluorine-doped tin oxide (FTO) substrates from dimethyl sulfoxide solution and the effects of the Cd and Ag alloying on device performance.

Improving the performance of kesterite solar cells by solution germanium alloying.

Cation substitution is an effective strategy to regulate the defects/electronic properties of kesterite CuZnSn(S,Se) (CZTSSe) absorbers and improve the device photovoltaic performance. Here, we report Ge alloying kesterite CuZn(Sn,Ge)(S,Se) (CZTGSSe) a solution approach. The results demonstrate that the same chemical reaction of Ge to Sn ensures homogeneous Ge incorporation in the whole range of concentrations (from 0 to unit).

A facile synthesis of a copper(I) thiourea sulphate complex and its application for highly efficient chalcopyrite solar cells.

The precursor compound plays a crucial role in the development of low-cost chalcogenide thin-film solar cells a solution approach. In this work, we report on the synthesis of a new complex [Cu((NH)CS)]SO·HO through a simple redox reaction between inexpensive Cu(CHCOO)·HO and thiourea (TU) in water. Using this complex as a copper source, a stable dimethylformamide solution was made and copper indium sulfoselenide CuIn(S,Se) thin film solar cells with a high efficiency of 12.

Enhancing Performance and Stability of Perovskite Solar Cells through Surface Defect Passivation with Organic Bidentate Lewis Bases.

Organic Lewis bases [2,2'-bipyridine (BPY), 4-hydroxy-1,5-naphthyridine-3-carbonitrile (DQCN), and thenoyltrifluoroacetone (TTFA)] with bi-coordination sites of N and O were employed as perovskite surface defect passivants to address the efficiency and stability issues of perovskite solar cells (PSCs), with typical phenethylammonium iodide (PEAI) and piperazinium iodide (PI) passivants as reference. The surface properties of the perovskite films before and after passivation were characterized by Fourier-transform infrared, ultraviolet-visible, photoluminescence (PL), and time-resolved PL spectroscopy, X-ray diffraction, ultraviolet photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy. The characterizations reveal that BPY, DQCN, or TTFA forms coordination bonds with exposed "Pb", leading to a slight decrease in the highest occupied molecular orbital or lowest unoccupied molecular orbital energy level and bandgap.

Catalyst-Free [4+2] Cycloaddition of Ynamides with 2-Halomethyl Phenols To Construct 2-Amino-4-Chromenes and α-Halo Enamides Simultaneously.

We report the development of a facile protocol for the [4+2] cycloaddition of ynamides and 2-halomethyl phenols to afford the corresponding 2-amino-4-chromenes and α-halo enamides under catalyst-free conditions. The reaction proceeds under mild conditions and exhibits good tolerance toward various functional groups and generates high yields. The plausible mechanism involves the formation of an active intermediate keteniminium as well as -methylene quinone.

Color-Stable White Organic Light-Emitting Diodes Utilizing a Blue-Emitting Electron-Transport Layer.

We have fabricated efficient and color-stable white organic light-emitting diodes (WOLEDs) based on a simple double-layer device structure consisting of a blue-emitting oligoquinoline electron-transport layer and a poly(-vinyl carbazole) layer doped with phosphorescent green and red iridium emitters. Pure white color with the CIE coordinates from (0.30, 0.

Quantum Yields over 80% Achieved in Luminescent Europium Complexes by Employing Diphenylphosphoryl Tridentate Ligands.

Four tridentate europium(III) complexes containing a diphenylphosphoryl group are prepared with strong bonding between the ligands and centered ion, convinced by crystal structures. Compared to their parent bidentate complexes, the tridentate complexes display improved and exceptionally high photoluminescence quantum yields (PLQYs) in powder (all over 80%, best 91%), as well as in a CHCl solution and poly(methyl methacrylate) films, benefiting from compact, stable, and saturated coordination.

Water-Soluble and Highly Luminescent Europium(III) Complexes with Favorable Photostability and Sensitive pH Response Behavior.

Two highly luminescent and water-soluble Eu(III) complexes, Eu1 and Eu2, based on novel carboxyl-functionalized 1,5-naphthyridine derivatives 8-hydroxy-1,5-naphthyridine-2-carboxylic acid (HL1) and 7-cyano-8-hydroxy-1,5-naphthyridine-2-carboxylic acid (HL2), respectively, are designed and synthesized. The crystal structure of Eu2 indicates that the central Eu(III) ion is nine-coordinated by three tridentate ligands (O^N^O). Both Eu1 and Eu2 show strong luminescence in aqueous solution with quantum yields (lifetimes) of 28% (1.

A Strategy to Simplify the Preparation Process of Perovskite Solar Cells by Co-deposition of a Hole-Conductor and a Perovskite Layer.

The feasibility of co-depositing a hole-conductor and a perovskite layer is demonstrated to simplify the preparation process of perovskite solar cells. The CuSCN incorporated in the perovskite layer can participate in forming the perovskite/CuSCN bulk-heterojunction and accelerate hole transport effectively, which eventually leads to a maximum power conversion efficiency of 18.1% with almost no J-V hysteresis.

A Hexakis Terpyridine-Fullerene Ligand in Six-Fold Ruthenium, Iridium, and Iron Complexes: Synthesis and Electrochemical Properties.

An unprecedented straightforward route to six-fold terpyridine ligands around C60 , the latter being regioselectively functionalized in pseudo-octahedral positions using a six-fold Bingel reaction, is reported. Ruthenium, iridium, and iron complexes have been synthesized, and unambiguously characterized by NMR, MS, and cyclic voltammetry.

High-performance inverted planar heterojunction perovskite solar cells based on a solution-processed CuOx hole transport layer.

Unlabelled: During the past several years, methylammonium lead halide perovskites have been widely investigated as light absorbers for thin-film photovoltaic cells. Among the various device architectures, the inverted planar heterojunction perovskite solar cells have attracted special attention for their relatively simple fabrication and high efficiencies. Although promising efficiencies have been obtained in the inverted planar geometry based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) sulfonic acid (

Pedot: PSS) as the hole transport material (HTM), the hydrophilicity of the

Pedot: PSS is a critical factor for long-term stability.

Solution-Processed CuS NPs as an Inorganic Hole-Selective Contact Material for Inverted Planar Perovskite Solar Cells.

Organic-inorganic hybrid perovskite solar cells (PSCs) have drawn worldwide intense research in recent years. Herein, we have first applied another p-type inorganic hole-selective contact material, CuS nanoparticles (CuS NPs), in an inverted planar heterojunction (PHJ) perovskite solar cell. The CuS NP-modification of indium tin oxide (ITO) has successfully tuned the surface work function from 4.

Direct Observation of Long Electron-Hole Diffusion Distance in CH3NH3PbI3 Perovskite Thin Film.

In high performance perovskite based solar cells, CH3NH3PbI3 is the key material. We carried out a study on charge diffusion in spin-coated CH3NH3PbI3 perovskite thin film by transient fluorescent spectroscopy. A thickness-dependent fluorescent lifetime was found.

Controllable and Reversible Dispersiblity of Graphene Materials by a Generic Organometallic Functionalization.

A general and reversible functionalization method has been developed for reduced graphene oxide (rGO) based on a simple reaction sequence. In this sequence, the chemical functionalization of reduced graphene oxide (rGO) was first carried out by a nucleophilic addition of n-butyllithium (n-BuLi) to rGO sheets, followed by a subsequent coupling step of intermediates (n-Bu-rGO)n-Li(n+) with alkyl halide, leading to functionalized rGO with controllable and reversible dispersiblity in either nonpolar or polar solvents depending on the functional groups. Next, the functional groups could be reversibly removed by solvothermal treatment to generate reduced graphene sheets.

Facile and Effective Functionalization of Graphene Oxide by Boron-Oxygen Covalent or Bingel Cyclopropanation Reaction.

Functionalized graphene oxide (GO-BPh2), was obtained via one step reaction between triphenyl boron and oxygen-containing groups on graphene sheets. In addition, functionalized graphene oxide (GO-Carbene) was obtained via bingel cyclopropanation reaction of active double bands on graphene sheets. Both functionalized materials can be homogeneously distributed into ortho-dichlorobenene.

CuSCN-Based Inverted Planar Perovskite Solar Cell with an Average PCE of 15.6%.

Although inorganic hole-transport materials usually possess high chemical stability, hole mobility, and low cost, the efficiency of most of inorganic hole conductor-based perovskite solar cells is still much lower than that of the traditional organic hole conductor-based cells. Here, we have successfully fabricated high quality CH3NH3PbI3 films on top of a CuSCN layer by utilizing a one-step fast deposition-crystallization method, which have lower surface roughness and smaller interface contact resistance between the perovskite layer and the selective contacts in comparison with the films prepared by a conventional two-step sequential deposition process. The average efficiency of the CuSCN-based inverted planar CH3NH3PbI3 solar cells has been improved to 15.

Synthesis of highly functionalized C60 fullerene derivatives and their applications in material and life sciences.

Highly functionalized fullerenes can be efficiently constructed by various techniques. However, the challenge is to synthesize highly symmetrical fullerenes. Recently, a number of X-ray structures have been disclosed showing the high symmetry of substituted fullerenes.

Individualized rituximab treatment for relapsing neuromyelitis optica: a pediatric case report.

Background: Neuromyelitis optica is an autoimmune inflammatory disorder of the central nervous system. Current therapeutic approaches are based on small uncontrolled trials, case series, or case reports. There are only a few case reports describing rituximab for pediatric neuromyelitis optica.

Environmentally friendly approaches toward the production of processable graphene by exfoliation of graphite using ionic liquid.

A facile, low-cost and environmentally friendly method was developed to prepare processable graphene materials by direct exfoliation of expandable graphite flakes under wet ball milling conditions in ionic liquids. The graphene nano-sheets obtained in this method were characterized by AFM, Raman spectroscopy, UV-NIR. Thin-film field-effect transistors made from this graphene sheets exhibit ambipolar effect, an average hole mobility of -0.

Rapid and effective functionalization of graphene oxide by ionic liquid.

Functionalized graphene oxide (DDIB-GO) sheets, which can be homogeneously distributed into ortho-dichlorobenene, were obtained via rapid and effective covalent functionalization with imidazolium ionic liquids (1,3-didodecylimidazolium bromine) through ion exchange. The resulting DDIB-GO sheets were characterized by Fourier transform infrared spectroscopy (FTIR), UV Vis NIR spectroscopy, X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM), Atomic force microscopy (AFM). Furthermore, FTIR, XPS and TGA show that the 1,3-didodecylimidazolium have been covalently attached to the GO sheets.