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Performance of hole transporting material (HTM) plays a fundamental role in estimating overall efficiency of perovskite solar cell (PSC). Dopant free HTMs with high intrinsic hole mobility and stability have been emerged as a fascinating choice for production of highly efficient and stable PSCs. Here, we report facile synthesis and implementation of a novel tetrathiafulvalene (TTF) derivative as a dopant free HTM for efficient and ambient stable PSC. The PSC based on dopant free TTF HTM shows remarkable photovoltaic efficiency of 15.66% which is one of highest value for any TTF based HTM. Beside efficiency, PSC based on TTF HTM shows only about 16% decline in initial efficiency even after 45 days storage in ambient conditions without any encapsulation which verifies its excellent ambient stability and hydrophobicity. Furthermore, various physical, electrochemical, photovoltaic and optical parameters of TTF HTM are investigated by highly specialized characterization tools. We affirm these results will be helpful for developing novel HTMs for highly efficient and stable PSCs in future.

A new type of BODIPY dye, compound 2 which possesses donor-acceptor (D-A) type structure, is synthesized by decorating electron-rich THDTAP unit onto the meso-position of BODIPY. The THDTAP has two chemically active sites (S and N atoms) that are utilized to manipulate the optoelectronic properties. By stepwise oxidation of two S-atoms on THDTAP moiety with m-CPBA, the 2 was converted to 3, trans-4, syn-4, 5, and 6. This transformation results in large influence on optoelectronic properties. The theoretical calculations reveal that the LUMOs of 2–6 are all located on BODIPY core, whereas their HOMOs show the different distributions. The 2 and 3 show the intramolecular charge-transfer (ICT) transition as proved by TD-DFT calculations, red-shifts of absorption and emission bands, and solvatochromism. The ICT process is inhibited in trans-4, syn-4, 5, and 6 due to the high oxidation states of S-atoms on THDTAP moieties. As a result, these four compounds display characteristic fluorescence of BODIPY. The femtosecond transient absorption (fs-TA) spectroscopic study reveals that 2 shows photoinduced hole-transfer (PHT) process in dichloromethane (DCM) solution. Upon acidification and neutralization of N-atom on THDTAP moiety, the ICT/PHT process of 2 in DCM is reversibly manipulated to result in fluorescence ON/OFF of BODIPY core. Moreover, the fluorescence of BODIPY core on 2 can be switched on through electrochemical oxidation of N-atom on THDTAP moiety. The compound 2 is thus a promising fluorometric sensor toward peroxide, acid, and electrochemical stimuli.

The conjugated polycycles show excellent optical and electrical properties that are suitable for application in various organic electronics. While most of attentions have been paid to polycycles having planar pi-conjugated system, the curved polycycles seem amazing due to their unique physical and chemical features. The non-planar conjugated polycycles have been created with the geometries of bracelet, saddle, bowl, Mobius band, helicenes, etc. Among them, the bowl-shaped one is of growing interest owing to the multidiscipline applications such as synthetic intermediates for end-cap of carbon nanotube, coordination with metal ions, encapsulation of fullerenes, and fabrication of electronic devices. In this paper, we summarize the recent advances on the chemistry of the bowl-shaped conjugated polycycles, particularly on their synthesis and the further chemical modifications toward organic functional materials. (C) 2016 Chinese Chemical Society and Institute of Materia-Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

The preparation, crystal structures, and physical properties of magnetic organic conductors based on a new bent donor molecule ethylenedithio-ethylenediseleno-tetrathiafulvalene-thioquinone-1,3-dithiolemethide (EDT-EDSe-TTFVS 3 ) are reported. The single crystals of 3 2 FeCl 4 (EtOH) and 3 2 FeBr 4 are obtained by the electrochemical oxidation of 3 in the presence of ( n -Bu 4 N)FeX 4 (X = Cl, Br) at 45 °C. Semiconducting behavior is observed with moderate conductivities of 4.0 and 0.6 S cm −1 for 3 2 FeCl 4 (EtOH) and 3 2 FeBr 4 , respectively. In the crystal structures of both salts, the donor molecules and magnetic FeX 4 − ions form segregated layers. Within the organic layer, the donor molecules form columnar stacks, and the intra-columnar intermolecular overlap integrals are larger than the inter-columnar ones, resulting in the quasi one-dimensional electronic structures. There are atomic close contacts between the donor and FeX 4 ion layers, which gives rise to the antiferromagnetic interaction of Fe(III) d -spins in both salts. Moreover, the Fe(III) d -spins in 3 2 FeBr 4 are subject to the antiferromagnetic ordering at 5 K due to the strong π– d and d–d interactions.

The introduction of a methyl group into ethylenedioxytetrathiafulvalene (EDO-TTF) greatly modified the molecular character as a component for the conducting complexes. While the pristine EDO-TTF almost exclusively formed head-to-tail type overlapping with the neighboring donor molecules in the complexes, the methyl substituted compound, MeEDO-TTF, showed both the head-to-head and head-to-tail overlapping patterns. In the former case, the donor molecules interacted with each other in a two-dimensional fashion to provide stable metals along with the charge-ordered complex which exhibited semiconductor-semiconductor first-order transition just above room temperature. The overlapping pattern of MeEDO-TTF directly corresponded to the electronic structure of the complex. In the case of head-to-tail packing patterns, the charge carriers were delocalized only in a quasi-one-dimensional column or in a multimer composed of the donor molecules. The comparison of the intermolecular overlap integrals calculated in the extended Huckel level suggested that at least the magnitude of ca. 10×10−3 is needed for the infinite chain or network of the conducting component molecules to exhibit metallic nature.

Ternary radical cation salts containing ethylenedioxytetrathiafulvalene, its mono-methyl substituted derivative, and hexafluorophosphate, [(EDO-TTF) 1– x (MeEDO-TTF) x ] 2 PF 6 ( x =mole fraction of MeEDO-TTF, x =0.01–0.13) were prepared by electrooxidation. Mole fractions of EDO-TTF and MeEDO-TTF in EDO-TTF rich alloys were consistent with the donor mixing ratios in preparation. Crystal structures of these alloys at room temperature were isostructural to that of (EDO-TTF) 2 PF 6 , where the donor molecules formed a nearly uniform stacking column to give a quasi-one-dimensional Fermi surface. The alloys exhibited a metal–insulator transition with tetramerization within the donor stack and anion-ordering. Temperature-variable structural analysis and Raman spectra revealed that the charge-ordering took place in the low temperature phase of x =0.05 alloy, however, this feature vanished in the x =0.13 alloy. The phase transition temperature decreased with increasing x value from 279 K of pristine (EDO-TTF) 2 PF 6 to 188 K of x =0.13 alloy.

Electrical and magnetic properties of TmCoIn 5 and YbCoIn 5 single crystals were investigated by means of electrical resistivity and magnetization measurements in the temperature range from 300 to 0.5 K under the magnetic field up to 5 T. TmCoIn 5 is an antiferromagnetic metal with a Neel temperature T N =2.6 K. YbCoIn 5 shows non-magnetic behavior, reflecting of divalent Yb ion.

A bromo- and chlorodecarboxylation of various aromatic carboxylic acids catalyzed by Pd(II) has been developed in this work. A series of electron-rich arenecarboxylic acids gave the corresponding decarboxylative monohalogenation products under the typical reaction conditions.

We examined the ultrafast response of the metallic high-temperature phase in the conducting charge transfer complex (EDO-TTF)2PF6. A large reflectivity change of approximately 10% was observed when the intra-molecular band was excited by a weak 3.1 eV ultraviolet light pulse. The lifetimes of the photo-induced states were 0.2 and 0.7 ps in the Drude-like band and the intra-molecular band, respectively. Measurement of the photo-induced spectrum just after photo-excitation and simulation using the Drude model revealed that the electronically excited EDO-TTF molecules shortened the relaxation time of conduction electrons and reduced the reflectivity of the Drude-like band.