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1.
《Arabian Journal of Chemistry》2022,15(1):103536
These days, an important concern in water contamination is the remaining dyes from various sources (for instance, dye and dye intermediates industries, pulp and paper industries, textile industries, craft bleaching industries, tannery, and pharmaceutical industries, etc.), and a broad range of persistent organic contamination has been entered to the wastewater treatment systems or natural water supplies. Indeed, it is extremely hazardous and toxic to the living organism. Therefore, it is necessary to remove these organic pollutants before releasing them into the environment. Photocatalysis is a quickly growing technology for sewage procedures. For this purpose, Cu2HgI4 nanostructures were prepared via facile, and cost-effective sonochemical method. The effect of varied circumstances, such as various surfactants, sonication power, and sonication time was considered on the crystallinity, structure, shape, and particle size of products. Cu2HgI4 possesses a suitable bandgap (2.2 eV) in the visible area. The photocatalytic performance of the Cu2HgI4 was surveyed for the elimination of various organic dyes under visible radiation and exposed that this compound could degrade and remove methyl orange about 94.2% in an acidic medium after 160 min under visible light. Besides, the result showed that various parameters, including, pH, dye concentration, types of dyes, catalyst dosages, and time of irradiation affected the photocatalytic efficiency. 相似文献
2.
Back Cover: Understanding the Origins of Nucleophilic Hydride Reactivity of a Sodium Hydride–Iodide Composite (Chem. Eur. J. 21/2016) 下载免费PDF全文
3.
Bingchu Tian Dr. Yanbo Shang Yi Tu Dr. Jun Hu Dr. Dong Han Qian Xu Prof. Shangfeng Yang Prof. Yifan Ye Dr. Honghe Ding Dr. Yu Li Prof. Junfa Zhu 《Chemphyschem》2023,24(20):e202300400
The interfacial electronic structure of perovskite layers and transport layers is critical for the performance and stability of perovskite solar cells (PSCs). The device performance of PSCs can generally be improved by adding a slight excess of lead iodide (PbI2) to the precursor solution. However, its underlying working mechanism is controversial. Here, we performed a comprehensive study of the electronic structures at the interface between CH3NH3PbI3 and C60 with and without the modification of PbI2 using in situ photoemission spectroscopy measurements. The correlation between the interfacial structures and the device performance was explored based on performance and stability tests. We found that there is an interfacial dipole reversal, and the downward band bending is larger at the CH3NH3PbI3/C60 interface with the modification of PbI2 as compared to that without PbI2. Therefore, PSCs with PbI2 modification exhibit faster charge carrier transport and slower carrier recombination. Nevertheless, the modification of PbI2 undermines the device stability due to aggravated iodide migration. Our findings provide a fundamental understanding of the CH3NH3PbI3/C60 interfacial structure from the perspective of the atomic layer and insight into the double-edged sword effect of PbI2 as an additive. 相似文献
4.
Michael G. Pfeffer Tanja Kowacs Dr. Maria Wächtler Dr. Julien Guthmuller Prof. Dr. Benjamin Dietzek Prof. Dr. Johannes G. Vos Prof. Dr. Sven Rau 《Angewandte Chemie (International ed. in English)》2015,54(22):6627-6631
A molecular photocatalyst consisting of a RuII photocenter, a tetrapyridophenazine bridging ligand, and a PtX2 (X=Cl or I) moiety as the catalytic center functions as a stable system for light‐driven hydrogen production. The catalytic activity of this photochemical molecular device (PMD) is significantly enhanced by exchanging the terminal chlorides at the Pt center for iodide ligands. Ultrafast transient absorption spectroscopy shows that the intramolecular photophysics are not affected by this change. Additionally, the general catalytic behavior, that is, instant hydrogen formation, a constant turnover frequency, and stability are maintained. Unlike as observed for the Pd analogue, the presence of excess halide does not affect the hydrogen generation capacity of the PMD. The highly improved catalytic efficiency is explained by an increased electron density at the Pt catalytic center, this is confirmed by DFT studies. 相似文献
5.
Sulfonyl Ketenimines as Key Intermediates in One‐Pot Synthesis of N‐Sulfonyl‐2‐alkaneimidoyl Selenocyanates 下载免费PDF全文
Sulfonyl‐ketenimine intermediates, generated by the addition of Cu acetylides to sulfonyl azides, are trapped by KSeCN to afford N‐sulfonyl‐2‐alkaneimidoyl selenocyanates in moderate‐to‐good yields. 相似文献
6.
7.
Equilibria of EuO dissolution and dissociation in molten (NaBr + NaI) mixtures of 0.77:0.23 and 0.31:0.69 compositions at T = 973 K were studied by potentiometric titration method using Pt(O2)|ZrO2(Y2O3) indicator electrode. The solubility product indices of EuO are (7.81 ± 0.08) and (8.43 ± 0.16) in the melts of 0.77:0.23 and 0.31:0.69 compositions. The corresponding dissociation constant indices are (4.96 ± 0.04) and (5.54 ± 0.06), respectively (all the parameters are in molality). Non-dissociated EuO is the prevailing form in all the saturated solutions of europium monoxide. The decrease of the iodide ion concentration in the melts results in strengthening of EuO dissociation that is explained by introduction of harder Pearson’s base (Br−) in sodium iodide melt. In its turn this increases the fixation degree of Eu2+ in mixed halide complexes. The total solubility of EuO decreases going from NaI melt to the (bromide + iodide) mixtures that is caused by the decrease of ‘physical’ solubility of non-dissociated oxide which occupies hollow spaces of enough large size in the ionic solvents. The quantity of these hollow spaces diminishes at the sequential Br− → I− substitution. 相似文献
8.
研究了端基烯烃和醛肟在氧化剂过硫酸氢钾和催化量碘代烷烃作用下的[3+2]环合反应,合成了一系列具有良好产率及区域选择性的3,5-二取代异噁唑啉化合物.反应中,碘代烷烃先经过氧化分解产生了活泼的次碘酸,再依次与醛肟和烯烃经亲电加成反应生成五元杂环碘代中间体,该中间体通过消除反应得到3,5-二取代异噁唑啉化合物.考察了反应条件的影响,提出了可能的反应机理,为合成3,5-二取代异噁唑啉化合物提供了新方法. 相似文献
9.
合成得到了2个新的有机-无机杂化化合物{(4-CH3-Bz-4-Ph-Py)[PbI3]}n(1)(其中4-CH3-Bz-4-Ph-Py是4-甲基苄基-4-苯基吡啶阳离子)和{(4-CF3-Bz-4-Ph-Py)[PbI3]}n(2)(其中4-CF3-Bz-4-Ph-Py是4-三氟甲基苄基-4-苯基吡啶阳离子)。对化合物1和2进行了元素分析、粉末X射线衍射等表征,并利用X射线单晶衍射测定了它们的单晶结构。化合物1属于正交晶系,P21212空间群;化合物2与1同构。结构研究表明,化合物1和2中,铅碘八面体通过共边连接方式,形成[Pb3I9]n三链,有机阳离子填充在无机碘化铅链空隙中。 相似文献
10.
《Electroanalysis》2017,29(5):1316-1323
Total antioxidant capacity is an important parameter for the evaluation of the oxidative status in different kinds of biological samples such as plant extracts, or in food industry. We report a fast, easy, portable, cost‐effective electroanalytical method to measure total antioxidant capacity, based on the reaction of natural antioxidants with electrogenerated iodine using disposable platinum screen‐printed electrodes. This reaction can be measured by the increment of the electrochemical current signal of iodide oxidation to iodine during a voltammetric cycle. Iodine reacts with reducing compounds such as glutathione, ascorbate, gallic acid and NADH without interference of the corresponding oxidized counter‐parts. The addition of ascorbate oxidase also allows the concentration of ascorbate to be determined. The method was tested with real samples of plant extracts and the results correlated well with those obtained with a standard spectrophotometric method. 相似文献