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31.
Iwan Zimmermann Sadig Aghazada Mohammad Khaja Nazeeruddin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(4):1084-1088
Organic‐inorganic hybrid perovskites have attracted great attention over the last few years as potential light‐harvesting materials for efficient and cost‐effective solar cells. However, the use of lead iodide in state‐of‐the‐art perovskite devices may demonstrate an obstacle for future commercialization due to toxicity of lead. Herein we report on the synthesis and characterization of low dimensional tin‐based perovskites. We found that the use of symmetrical imidazolium‐based cations such as benzimidazolium (Bn) and benzodiimidazolium (Bdi) allow the formation of 2D perovskites with relatively narrow band gaps compared to traditional ‐NH3+ amino groups, with optical band gap values of 1.81 eV and 1.79 eV for Bn2SnI4 and BdiSnI4 respectively. Furthermore, we demonstrate that the optical properties in this class of perovskites can be tuned by formation of a quasi 2D perovskite with the formula Bn2FASn2I7. Additionally, we investigate the change in band gap in the mixed Sn/Pb solid solution Bn2SnxPbx?1I4. Devices fabricated with Bn2SnI4 show promising efficiencies of around 2.3 %. 相似文献
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Juveriya Farooq Rokeya Sultana Tahreen Taj Syed Mohammed Basheeruddin Asdaq Abdulkhaliq J. Alsalman Mohammed Al Mohaini Maitham A. Al Hawaj Mehnaz Kamal Saad Alghamdi Mohd. Imran Haleema Shahin Ruheena Tabassum 《Molecules (Basel, Switzerland)》2022,27(1)
The drugs used to treat cancer not only kill fast-growing cancer cells, but also kill or slow the growth of healthy cells, causing systemic toxicities that lead to altered functioning of normal cells. Most chemotherapeutic agents have serious toxicities associated with their use, necessitating extreme caution and attention. There is a growing interest in herbal remedies because of their pharmacological activities, minimal side effects, and low cost. Thymoquinone, a major component of the volatile oil of Nigella sativa Linn, also known as black cumin or black seeds, is commonly used in Middle Eastern countries as a condiment. It is also utilized for medicinal purposes and possesses antidiabetic, anti-cancer, anti-inflammatory, hepatoprotective, anti-microbial, immunomodulatory, and antioxidant properties. This review attempts to compile the published literature demonstrating thymoquinone’s protective effect against chemotherapeutic drug-induced toxicities. 相似文献
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Luis A. Illicachi Javier Urieta-Mora Dr. Joaquín Calbo Dr. Juan Aragó Cansu Igci Dr. Inés García-Benito Dr. Cristina Momblona Prof. Dr. Braulio Insuasty Prof. Dr. Alejandro Ortiz Dr. Cristina Roldán-Carmona Dr. Agustín Molina-Ontoria Prof. Dr. Enrique Ortí Prof. Dr. Nazario Martín Prof. Dr. Mohammad Khaja Nazeeruddin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(48):11039-11047
Three novel donor–π-bridge–donor (D -π-D) hole-transporting materials (HTMs) featuring triazatruxene electron-donating units bridged by different 3,4-ethylenedioxythiophene (EDOT) π-conjugated linkers have been synthesized, characterized, and implemented in mesoporous perovskite solar cells (PSCs). The optoelectronic properties of the new dumbbell-shaped derivatives (DTTXs) are highly influenced by the chemical structure of the EDOT-based linker. Red-shifted absorption and emission and a stronger donor ability were observed in passing from DTTX-1 to DTTX-2 due to the extended π-conjugation. DTTX-3 featured an intramolecular charge transfer between the external triazatruxene units and the azomethine–EDOT central scaffold, resulting in a more pronounced redshift. The three new derivatives have been tested in combination with the state-of-the-art triple-cation perovskite [(FAPbI3)0.87(MAPbBr3)0.13]0.92[CsPbI3]0.08 in standard mesoporous PSCs. Remarkable power conversion efficiencies of 17.48 % and 18.30 % were measured for DTTX-1 and DTTX-2 , respectively, close to that measured for the benchmarking HTM spiro-OMeTAD (18.92 %), under 100 mA cm−2 AM 1.5G solar illumination. PSCs with DTTX-3 reached a PCE value of 12.68 %, which is attributed to the poorer film formation in comparison to DTTX-1 and DTTX-2 . These PCE values are in perfect agreement with the conductivity and hole mobility values determined for the new compounds and spiro-OMeTAD. Steady-state photoluminescence further confirmed the potential of DTTX-1 and DTTX-2 for hole-transport applications as an alternative to spiro-OMeTAD. 相似文献
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Kessler F Costa RD Di Censo D Scopelliti R Ortí E Bolink HJ Meier S Sarfert W Grätzel M Nazeeruddin MK Baranoff E 《Dalton transactions (Cambridge, England : 2003)》2012,41(1):180-191
Herein we report a series of charged iridium complexes emitting from near-UV to red using carbene-based N^C: ancillary ligands. Synthesis, photophysical and electrochemical properties of this series are described in detail together with X-ray crystal structures. Density Functional Theory calculations show that the emission originates from the cyclometallated main ligand, in contrast to commonly designed charged complexes using bidentate N^N ancillary ligands, where the emission originates from the ancillary N^N ligand. The radiative process of this series of compounds is characterized by relatively low photoluminescence quantum yields in solution that is ascribed to non-radiative deactivation of the excited state by thermally accessible metal-centered states. Despite the poor photophysical properties of this series of complexes in solution, electroluminescent emission from the bluish-green to orange region of the visible spectrum is obtained when they are used as active compounds in light-emitting electrochemical cells. 相似文献
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A Computational and Experimental Study of Thieno[3,4‐b]thiophene as a Proaromatic π‐Bridge in Dye‐Sensitized Solar Cells 下载免费PDF全文
George A. Puneky Dr. Amala Dass Dr. Shaik M. Zakeeruddin Prof. Mohammad Khaja Nazeeruddin Prof. Michael Grätzel Prof. Gregory S. Tschumper Prof. Jared H. Delcamp 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):694-703
Four D ‐π‐A dyes (D=donor, A=accpetor) based on a 3,4‐thienothiophene π‐bridge were synthesized for use in dye‐sensitized solar cells (DSCs). The proaromatic building block 3,4‐thienothiophene is incorporated to stabilize dye excited‐state oxidation potentials. This lowering of the excited‐state energy levels allows for deeper absorption into the NIR region with relatively low molecular weight dyes. The influence of proaromatic functionality is probed through a computational analysis of optimized bond lengths and nucleus independent chemical shifts (NICS) for both the ground‐ and excited‐ states. To avoid a necessary lowering of the TiO2 semiconductor conduction band (CB) to promote efficient dye–TiO2 electron injection, strong donor functionalities based on triaryl‐ and diarylamines are employed in the dye designs to raise both the ground‐ and excited‐state oxidation potentials of the dyes. Solubility, aggregation, and TiO2 surface protection are addressed by examining an ethylhexyl alkyl chain in comparison to a simple ethyl chain on the 3,4‐thienothiophene bridge. Power conversion efficiencies of up to 7.8 % are observed. 相似文献
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Dr. Lauren E. Polander Dr. Aswani Yella Basile F. E. Curchod Negar Ashari Astani Dr. Joël Teuscher Rosario Scopelliti Dr. Peng Gao Dr. Simon Mathew Prof. Jacques‐E. Moser Dr. Ivano Tavernelli Prof. Ursula Rothlisberger Prof. Michael Grätzel Dr. Md. Khaja Nazeeruddin Dr. Julien Frey 《Angewandte Chemie (International ed. in English)》2013,52(33):8731-8735
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Ghosh AK Kumaragurubaran N Hong L Lei H Hussain KA Liu CF Devasamudram T Weerasena V Turner R Koelsch G Bilcer G Tang J 《Journal of the American Chemical Society》2006,128(16):5310-5311
Structure-based design, synthesis, and X-ray structure of protein-ligand complexes of memapsin 2 are described. The inhibitors are designed specifically to interact with S2- and S3-active site residues to provide selectivity over memapsin 1 and cathepsin D. Inhibitor 6 has exhibited exceedingly potent inhibitory activity against memapsin 2 and selectivity over memapsin 1 (>3800-fold) and cathepsin D (>2500-fold). A protein-ligand crystal structure revealed cooperative interactions in the S2- and S3-active sites of memapsin 2. These interactions may serve as an important guide to design selectivity over memapsin 1 and cathepsin D. 相似文献
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Ito S Ha NL Rothenberger G Liska P Comte P Zakeeruddin SM Péchy P Nazeeruddin MK Grätzel M 《Chemical communications (Cambridge, England)》2006,(38):4004-4006
High-efficiency flexible dye-sensitized solar cells were fabricated with a Ti-metal foil substrate for photo anode and using a Pt-electrodeposited counter electrode on ITO/polyethylene naphthalate (ITO/PEN); these devices were characterized by incident photon-to-current efficiency (IPCE), optical transmittance and electrical impedance spectroscopy. 相似文献
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Javier Urieta‐Mora Ins García‐Benito Iwan Zimmermann Juan Arag Pedro D. García‐Fernndez Giulia Grancini Agustín Molina‐Ontoria Enrique Ortí Nazario Martín Mohammad Khaja Nazeeruddin 《Helvetica chimica acta》2019,102(4)
Two new hole‐transporting materials (HTMs), BX‐OMeTAD and BTX‐OMeTAD , based on xanthene and thioxanthene units, respectively, and bearing p‐methoxydiphenylamine peripheral groups, are presented for their use in perovskite solar cells (PSCs). The novelty of the newly designed molecules relies on the use of a single carbon‐carbon bond ‘C?C’ as a linker between the two functionalized heterocycles, which increases the flexibility of the molecule compared with the more rigid structure of the widely used HTM spiro‐OMeTAD. The new HTMs display a limited absorbance in the visible region, due to the lack of conjugation between the two molecular halves, and the chemical design used has a remarkably impact on the thermal properties when compared to spiro‐OMeTAD. BX‐OMeTAD and BTX‐OMeTAD have been tested in ([(FAPbI3)0.87(MAPbBr3)0.13]0.92[CsPbI3]0.08)‐based PSC devices exhibiting power conversion efficiencies of 14.19 and 16.55 %, respectively. The efficiencies reached, although lower than those measured for spiro‐OMeTAD (19.63 %), are good enough to consider the chemical strategy used as an interesting via to design HTMs for PSCs. 相似文献