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61.
卤化钙钛矿由于具有低成本、高效率等特点,最近作为非常有前景的太阳能电池吸收层材料被广泛研究。卤化钙钛矿型太阳能电池效率在短短的几年间由3.8%(2009年)迅速增加到22.1%(2016年)。卤化钙钛矿型太阳能电池的出现彻底改变了太阳能电池领域,不仅因为它们快速增长的效率,而且因为它们在材料生长和结构方面的可控性。卤化钙钛矿型太阳能电池的优越性能说明卤化钙钛矿材料具有独特的物理性质。在本综述中,我们总结了卤化钙钛矿材料最近几年在结构、电学、光学方面的理论研究成果,这些都与它们在太阳能电池方面的应用密切相关。我们也将探讨一些卤化钙钛矿型太阳能电池目前遇到的挑战以及可能的理论解决途径。 相似文献
62.
H. Dhaouadi H. Marouani M. Rzaigui A. Madani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1801-1814
Chemical preparation, crystal structure, thermogravimetric and differential analysis, solid state 31P MAS NMR characterization, and IR spectroscopic investigations are given for a new organic cation dihydrogenmonophosphate, (2-CH3OC6H4CH2NH3)H2PO4. This compound is monoclinic C2/c, with unit cell parameters a = 27.740(8), b = 4.827(2), c = 16.435(3) Å, β = 93.79(2)°, V = 2196 (1) Å3, Z = 8, and ρ = 1.422 g · cm?3. The crystal structure has been determined and refined to R = 0.046 (Rw = 0.056), using 1,746 independent reflections with I > 3σ (I). Its atomic arrangement can be described by infinite polyanions [H2PO4] n n ?, organized in ribbons alternating with organic cations. Strong hydrogen bonds connect the different components. Electrical conductivity measurements show that the [2-CH3OC6H4CH2NH3]H2PO4 has a low ionic conductivity value at 403 K. 相似文献
63.
Adel Mahroug Mohamed Belhouchet Annie Hémon-Ribaud Tahar Mhiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2332-2340
Abstract A new adduct 3-ammoniumphenyl sulfone dihydrogenphosphate phosphoric acid, [C12H14N2O2S](H2PO4)2H3PO4, has been synthesized by slow evaporation at room temperature using 3-aminophenyl sulfone as the structure-directing agent. The structure, determined by single-crystal X-ray diffraction at 293 K, can be described as inorganic layers built by H2PO4 ? groups and H3PO4 molecules, parallel to the (a, c) planes at y = 0.5, between which molecules of the organic group [C12H14N2O2S]2+ are inserted. In this atomic arrangement, hydrogen bonds and van der Waals interactions between the different species play an important role in the tri-dimensional network cohesion. Solid-state 13C and 31P MAS NMR spectroscopies are in agreement with the X-ray structure. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Tables S1 and S2. Figures S1 and S2.] GRAPHICAL ABSTRACT 相似文献
64.
《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1401-1410
Abstract Electrostatically layered aluminosilicate nanocomposites have been prepared by the sequential deposition of poly(allylamine hydrochloride)/poly(acrylic acid)/poly(allylamine hydrochloride)/saponite (PAH/PAA/PAH/saponite)10 on poly(ethylene terephtalate) (PET) film. Exfoliated saponite nanoplatelets were obtained by extensive shaking, sonication, and centrifugation of a water suspension. To minimize permeability and improve the mechanical integrity, cross‐linking of composite films was carried out at different temperatures. The formation of amide linkage induced through heating was observed by Fourier Transform Infrared (FT‐IR) and x‐ray photoelectron spectroscopy (XPS). The cross‐linking of nanocomposites (PAH/PAA/PAH/saponite)10 showed 60% decrease in permeability of oxygen when compared with the pristine PET substrate film. In contrast, water permeability of the nanocomposite membrane was not affected by heating temperature and deposition cycles. 相似文献
65.
66.
Excellent Performance of Few‐Layer Borocarbonitrides as Anode Materials in Lithium‐Ion Batteries
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Borocarbonitrides (BxCyNz) with a graphene‐like structure exhibit a remarkable high lithium cyclability and current rate capability. The electrochemical performance of the BxCyNz materials, synthesized by using a simple solid‐state synthesis route based on urea, was strongly dependent on the composition and surface area. Among the three compositions studied, the carbon‐rich compound B0.15C0.73N0.12 with the highest surface area showed an exceptional stability (over 100 cycles) and rate capability over widely varying current density values (0.05–1 A g?1). B0.15C0.73N0.12 has a very high specific capacity of 710 mA h g?1 at 0.05 A g?1. With the inclusion of a suitable additive in the electrolyte, the specific capacity improved drastically, recording an impressive value of nearly 900 mA h g?1 at 0.05 A g?1. It is believed that the solid–electrolyte interphase (SEI) layer at the interface of BxCyNz and electrolyte also plays a crucial role in the performance of the BxCyNz . 相似文献
67.
Visible‐Light‐Induced Generation of H2 by Nanocomposites of Few‐Layer TiS2 and TaS2 with CdS Nanoparticles
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Uttam Gupta Bolla Govinda Rao Urmimala Maitra Dr. B. E. Prasad Prof. C. N. R. Rao 《化学:亚洲杂志》2014,9(5):1311-1315
Graphene analogues of TaS2 and TiS2 (3–4 layers), prepared by Li intercalation followed by exfoliation in water, were characterized. Nanocomposites of CdS with few‐layer TiS2 and TaS2 were employed for the visible‐light‐induced H2 evolution reaction (HER). Benzyl alcohol was used as the sacrificial electron donor, which was oxidized to benzaldehyde during the reaction. Few‐layer TiS2 is a semiconductor with a band gap of 0.7 eV, and its nanocomposite with CdS showed an activity of 1000 μmol h?1 g?1. The nanocomposite of few‐layer TaS2, in contrast, gave rise to higher activity of 2320 μmol h?1 g?1, which was attributed to the metallic nature of few‐layer TaS2. The amount of hydrogen evolved after 20 and 16 h for the CdS/TiS2 and CdS/TaS2 nanocomposites was 14833 and 28132 μmol, respectively, with turnover frequencies of 0.24 and 0.57 h?1, respectively. 相似文献
68.
Dr. Jorge Pascual Dr. Diego Di Girolamo Marion A. Flatken Mahmoud H. Aldamasy Guixiang Li Dr. Meng Li Prof. Antonio Abate 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(12):e202103919
In 2020 dimethyl sulfoxide (DMSO), the ever-present solvent for tin halide perovskites, was identified as an oxidant for SnII. Nonetheless, alternatives are lacking and few efforts have been devoted to replacing it. To understand this trend it is indispensable to learn the importance of DMSO on the development of tin halide perovskites. Its unique properties have allowed processing compact thin-films to be integrated into tin perovskite solar cells. Creative approaches for controlling the perovskite crystallization or increasing its stability to oxidation have been developed relying on DMSO-based inks. However, increasingly sophisticated strategies appear to lead the field to a plateau of power conversion efficiency in the range of 10–15 %. And, while DMSO-based formulations have performed in encouraging means so far, we should also start considering their potential limitations. In this concept article, we discuss the benefits and limitations of DMSO-based tin perovskite processing. 相似文献
69.
Herein, we report a facile method for synthesizing MoCo-layered double hydroxide (LDH) nanosheets employing Prussian blue analog (PBA) as the precursor. The introduction of Mo in Co-LDH modulates the electronic structure, increases the number of active sites and electrochemical surface area to improve the hydrogen evolution, oxygen evolution, and overall water splitting activity. As a result, PBA-derived Mo0.25Co0.75-LDH nanosheets demonstrated 10 mA cm?2 current density at only 220 mV and 115 mV overpotentials for OER and HER, respectively. The overall water splitting was attained at 1.52 V cell voltage for 10 mA cm?2 current density. 相似文献
70.
Gustavo Pereira Saito Ana Carolina Lanfredi Matsumoto Renata Pires Assis Iguatemy Loureno Brunetti Marco Aurlio Cebim Marian Rosaly Davolos 《Molecules (Basel, Switzerland)》2021,26(8)
Excessive UV solar radiation exposure causes human health risks; therefore, the study of multifunctional filters is important to skin UV protective ability and also to other beneficial activities to the human organism, such as reduction of reactive oxygen species (ROS) responsible for cellular damages. Potential multifunctional filters were obtained by intercalating of ferulate anions into layered simple metal hydroxides (LSH) through anion exchange and precipitation at constant pH methods. Ultrasound treatment was used in order to investigate the structural changes in LSH-ferulate materials. Structural and spectroscopic analyses show the formation of layered materials composed by a mixture of LSH intercalated with ferulate anions, where carboxylate groups of ferulate species interact with LSH layers. UV-VIS absorption spectra and in vitro SPF measurements indicate that LSH-ferulate systems have UV shielding capacity, mainly UVB protection. The results of reactive species assays show the ability of layered compounds in capture DPPH•, ABTS•+, ROO•, and HOCl/OCl− reactive species. LSH-ferulate materials exhibit antioxidant activity and singular optical properties that enable their use as multifunctional filters. 相似文献