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| 1 | Encapsulating a Ni(Ⅱ) molecular catalyst in photoactive metal–organic framework for highly efficient photoreduction of CO2显示文摘Photocatalytic reduction of CO2 to CO is a promising strategy for reducing atmospheric CO2 levels and storing solar radiation as chemical energy.Here,we demonstrate that a molecular catalyst[NiⅡ(bpet)(H2O)2]successfully encapsulated into a highly robust and visible-light responsive metal–organic framework(Ru-UiO-67)to fabricate composite catalysts for photocatalytic CO2 reduction.The composite Ni@Ru-UiO-67 photocatalysts show efficient visible-light-driven CO2 reduction to CO with a TON of 581 and a selectivity of 99% after 20-h illumination,because of the facile electron transfer from Ru-photosensitizer to Ni(Ⅱ)active sites in Ni@Ru-UiO-67 system.The mechanistic insights into photoreduction of CO2 have been studied based on thermodynamical,electrochemical,and spectroscopic investigation,together with density functional theory(DFT)calculations.This work shows that encapsulating molecular catalyst into photoactive MOF highlights opportunities for designing efficient,stable and recyclable photocatalysts. | Zhi-Hao Yan Bo Ma Shu-Rong Li Junxue Liu Rong Chen Ming-Hao Du Shengye Jin Gui-Lin Zhuang La-Sheng Long Xiang-Jian Kong Lan-Sun Zheng | 2019 | Science Bulletin2019，64，14： | 5 |
| 2 | Bimetallic Nickel Cobalt Sulfide as E cient Electrocatalyst for Zn–Air Battery and Water Splitting显示文摘The development of e cient earth-abundant electrocatalysts for oxygen reduction, oxygen evolution, and hydrogen evolution reactions(ORR, OER, and HER) is important for future energy conversion and energy storage devices, for which both rechargeable Zn–air batteries and water splitting have raised great expectations. Herein, we report a single-phase bimetallic nickel cobalt sulfide((Ni,Co)S_2) as an e cient electrocatalyst for both OER and ORR. Owing to the synergistic combination of Ni and Co, the(Ni,Co)S_2 exhibits superior electrocatalytic performance for ORR, OER, and HER in an alkaline electrolyte, and the first principle calculation results indicate that the reaction of an adsorbed O atom with a H_2O molecule to form a *OOH is the potential limiting step in the OER. Importantly, it could be utilized as an advanced air electrode material in Zn–air batteries, which shows an enhanced charge–discharge performance(charging voltage of 1.71 V and discharge voltage of 1.26 V at 2 mA cm^(-2)), large specific capacity(842 mAh g_(Zn)^(-1) at 5 mA cm^(-2)), and excellent cycling stability(480 h). Interestingly, the(Ni,Co)S_2-based Zn–air battery can e ciently power an electrochemical water-splitting unit with(Ni,Co)S_2 serving as both the electrodes. This reveals that the prepared(Ni,Co)S_2 has promising applications in future energy conversion and energy storage devices. | Jingyan Zhang Xiaowan Bai Tongtong Wang Wen Xiao Pinxian Xi Jinlan Wang Daqiang Gao John Wang | 2019 | Nano-Micro Letters2019，11，1： | 4 |
| 3 | Visible–light driven photocatalytic degradation of bisphenol-A using ultrasonically synthesized polypyrrole/K-birnessite nanohybrids:Experimental and DFT studies显示文摘Although manganese oxides are known for their semiconductor characteristics, the photocatalytic performance of conducting polymer intercalated K-Birnessite(K-Bi) has not been explored till date. With the view to design a visible light driven organic–inorganic hybrid photocatalyst for rapid degradation of Bisphenol A(BPA), the present work reports the ultrasound-assisted green synthesis of K-Bi/polypyrrole(Ppy) nanohybrids. The loading of Ppy in K-Bi was confirmed by thermogravimetric analysis while the formation of organic–inorganic hybrid was confirmed by infrared spectroscopy. K-Bi revealed a band gap of 2.8 e V while for the nanohybrids it was found to be ranging between 2.4 and 1.6 e V. X-ray diffraction studies confirmed partial intercalation of Ppy chains in the inter-layer space of K-Bi. High resolution transmission electron microscopy and scanning electron microscopy studies showed mixed morphology of K-Birnessite/Ppy nanohybrids. Rapid degradation of BPA was observed under visible irradiation in presence of K-Bi/Ppy nanohybrids and almost90% degradation of 20 mg/L BPA solution was achieved within 120 min. The degradation was found to follow pseudo-first order kinetics and the degraded fragments were identified using liquid chromatography-mass spectrometry. Degradation pathway was proposed based on density-functional theory calculations of fukui index predicting the radical easyattacking(f0) and(f-) sites in BPA. | Jannatun Zia Mohamed Ajeer Ufana Riaz | 2019 | Journal of Environmental Sciences2019，31，5： | 2 |
| 4 | Contemplation on some cyclic N_8 isomers-A DFT treatment显示文摘Various cyclic N_8 isomers are considered at the levels of B3 LYP/6-311++G(d,p) and B3 LYP/c PVTZ. Some energies and molecular orbital properties are obtained. The structures are found to be stable in the singlet state but mostly unstable in the triplet. The heats of formation values calculated by means of T1 recipe reveals that they are highly endothermic. NICS(0) values have been calculated and aromaticity/antiaromaticity of the rings are discussed. Additionally, theoretical IR,UV-VIS spectra and the calculated impulse values have been obtained. | Lemi Türker | 2018 | Defence Technology(防务技术)2018，14，1： | 1 |
| 5 | Double dehydrogenation of carbocyclic β-dicarbonyl compounds:Koser's reagent can do what iodine(V) reagents can显示文摘Koser's reagent is found to be effective in the oxidative double dehydrogenation of various carbocyclic β-dicarbonyl compounds,which constitutes the first example on dehydrogenation reactivity of hypervalent iodine(Ⅲ) reagents for carbocyclic carbonyl compounds. DFT calculations reveal that the rate-determining step is the electrophilic addition of PhI+OH onto enolate of monodehydrogenated product. | Shan-Shan Liu Li Wang Ya-Nan Duan Ao Yu Chi Zhang | 2019 | Science China Chemistry2019，62，5： | 0 |
| 6 | Mechanism and origin of diastereoselectivity of N-heterocyclic carbene-catalyzed cross-benzoin reaction:A DFT study显示文摘Herein,the origin of the diastereoselectivity of N-heterocyclic carbene(NHC)-catalyzed cross-benzoin reactions between an a-amino aldehyde and furfural was studied by density functional theory.The computational results showed that the reaction proceeded through four steps:nucleophilic addition of NHC onto furfural,formation of a Breslow intermediate,cross-coupling reaction between Breslow intermediate and a-amino alde hyde,and dissociation of the catalyst.The cross-coupling was identified as the diaste reoselectivity-determining step,with the R-configured product generated preferentially.Noncovalent inte raction(NCI)analysis showed that the C-H…O and C-H…F inte ractions were responsible for determining the diastereoselectivity. | Yang Wang Yu Lan | 2020 | Chinese Chemical Letters2020，31，3： | 0 |
| 7 | A DFT study on TNGU isomers and aluminized cis-TNGU composites显示文摘Cis-and trans-1,3,4,6-tetranitroglycouril(TNGU, Sorguyl) have been considered for density functional treatment at the levels of B3LYP/6-31 G(d,p) and B3LYP/cc-PVDZ. Cis-TNGU has been found to be more stable than its trans isomer. Then, mono and dialuminized(cis-TNGU + Al and cis-TNGU+2Al) have been subjected to theoretical treatment at the level of B3LYP/6-31 + G(d). The spin states of the aluminized cis-TNGU composites have been considered as well. Although, cis-TNGU + Al(doublet) is found to be structurally stable, cis-TNGU+2Al singlet and triplet composites undergo certain bond cleavages.Structural and some quantum chemical properties, IR-UV spectra etc. have been presented. | Lemi Trker | 2018 | Defence Technology(防务技术)2018，14，2： | 0 |
| 8 | Electronic structures of halogen-doped Cu20 based on DFT calculationsElectronic structures of halogen-doped Cu20 based on DFT calculationsElectronic structures of halogen-doped Cu20 based on DFT calculations显示文摘In order to construct p-n homojunction of Cu20-based thin film solar cells that may increase its conversion efficiency, to synthesize n-type Cu20 with high conductivity is extremely crucial, and considered as a challenge in the near future. The doping effects of halogen on electronic structure of Cu20 have been investigated by density function theory calculations in the present work. Halogen dopants form donor levels below the bottom of conduction band through gaining or losing electrons, suggesting that halogen doping could make Cu20 have n-type conductivity. The lattice distortion, the impurity formation energy, the position, and the band width of donor level of Cu201-xHx (H = F, C1, Br, I) increase with the halogen atomic number. Based on the calculated results, chlorine doping is an effective n-type dopant for Cu20, owing to the lower impurity formation energy and suitable donor level. | 赵宗彦 易娟 周大成 | 2014 | Chinese Physics B2014，23，1： | 0 |
| 9 | Effect of the alkali metal(Li, Na, K) substitution on the geometric,electronic and optical properties of the smallest diamondoid: First principles calculations显示文摘In this study we employed the B3LYP/6-311++G(d,p) method combined with the CIS/6-311++G(d,p) calculation to investigate the effects of the type and the number of alkali metal atoms(Li, Na, K) on the geometric, electronic, and optical properties of alkali metals substituted into adamantanes. Substituting alkali metal(Li, Na, K)atoms caused significant changes in the electronic and optical properties of adamantane. The Ad-1Li, Ad-1Na,and Ad-1K structures showed a dramatically decreased energy gap and ionization potential, while adding more alkali metal atoms slightly decreased these properties. Substituting more alkali metals led to a shift in the maximum absorption wavelength from the visible to the infrared region, depending on the type of alkali metal atom substituted. The magnitude of shift occurred in the following order: Li b Na b K. These characteristics suggest the possibility of tunable electronic structures of this material for optoelectronic device applications. | Sriprajak Krongsuk Nikorn Shinsuphan Vittaya Amornkitbumrung | 2019 | Chinese Journal of Chemical Engineering2019，27，2： | 0 |
| 10 | Theoretical prediction on the reactivity of the Co-mediated intramolecular Pauson-Khand reaction for constructing bicyclo-skeletons in natural products显示文摘The Co_2(CO)_8-mediated intramolecular Pauson-Khand reaction is an efficient approach for constructing polycyclic skeletons. Recently, some of us reported a series of this type reactions involving stericallyhindered enynes for synthesizing natural products with reasonable reaction rates and yields. However,the reason for the high reactivity of the reaction remains unclear. We employed density functional theory calculations to clarify the mechanism and reactivity for this reaction. In contrast with chain olefin reactants, CO insertion is considered to be the rate-determining step for the overall Pauson-Khand reaction of cyclooctene derivatives. The reduced activation free energy for the alkene insertion step is attributed to: i) the electron-withdrawing group in close proximity to the C—C triple bond enhancing the reactivity of the alkyne moiety; ii) lower steric hindrance during alkene insertion when using the cyclooctene derivative. The effect of the substituent on the Co_2(CO)_8-mediated intramolecular PausonKhand reaction was then investigated. Internal alkenes exhibit lower reactivity than terminal alkenes because of the steric hindrance introduced by the substituted group. The cis internal alkene exhibits higher reactivity than the trans internal alkene. An ester group in close proximity to the C—C triple bond significantly enhances the reactivity. | Lei Zhu Zheyuan Wang Song Liu Tao Zhang Zhen Yang Ruopeng Bai Yu Lan | 2019 | Chinese Chemical Letters2019，30，4： | 0 |
| 11 | Destructive effect of magnesium and calcium atoms on TEX显示文摘The interaction of TEX(an explosive recently attracts attention) with Mg and Ca atom(s) has been investigated within the limitations of density functional theory at the level of B3 LYP/6-311 ++G(d,p). The effect of Mg in 1:1 mol ratio is very drastic on TEX and one of the NO_2 moieties is expelled as preform of nitrite ion. The second Mg atom in the composite(1:2 mol ratio of TEX:Mg) shows balancing effect of the first Mg atom, thus no bond cleavage occurs but some distortions happen. As for the effect of calcium, in1:1 and 1:2(TEX:Ca) ratios nitramine bond cleavage(s) occur(s) drastically. Some structural and quantum chemical data are presented. | Lemi Turker | 2017 | Defence Technology(防务技术)2017，13，5： | 0 |
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