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1.
One‐Pot Synthesis of Pomegranate‐Structured Fe3O4/Carbon Nanospheres‐Doped Graphene Aerogel for High‐Rate Lithium Ion Batteries 下载免费PDF全文
Dr. Dafang He Lixian Li Fengjuan Bai Chenyang Zha Prof. Liming Shen Prof. Harold H. Kung Prof. Ningzhong Bao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4454-4459
A unique hierarchically nanostructured composite of iron oxide/carbon (Fe3O4/C) nanospheres‐doped three‐dimensional (3D) graphene aerogel has been fabricated by a one‐pot hydrothermal strategy. In this novel nanostructured composite aerogel, uniform Fe3O4 nanocrystals (5–10 nm) are individually embedded in carbon nanospheres (ca. 50 nm) forming a pomegranate‐like structure. The carbon matrix suppresses the aggregation of Fe3O4 nanocrystals, avoids direct exposure of the encapsulated Fe3O4 to the electrolyte, and buffers the volume expansion. Meanwhile, the interconnected 3D graphene aerogel further serves to reinforce the structure of the Fe3O4/C nanospheres and enhances the electrical conductivity of the overall electrode. Therefore, the carbon matrix and the interconnected graphene network entrap the Fe3O4 nanocrystals such that their electrochemical function is retained even after fracture. This novel hierarchical aerogel structure delivers a long‐term stability of 634 mA h g?1 over 1000 cycles at a high current density of 6 A g?1 (7 C), and an excellent rate capability of 413 mA h g?1 at 10 A g?1 (11 C), thus exhibiting great potential as an anode composite structure for durable high‐rate lithium‐ion batteries. 相似文献
2.
Chih-Chieh Wang Ciao-Shin Tsai Gene-Hsiang Lee Su-Ying Chien Bo-Hao Chen Yu-Chun Chuang 《中国化学会会志》2023,70(5):1155-1167
Two d10 M(II) (M = Cd and Zn) coordination polymers (CPs) with chemical formulas, {[Cd(L1)(NCS)2(H2O)]⋅C2H5OH}n (1) , and {[Zn(L1)(NCS)2]⋅C2H5OH⋅0.5H2O}n (2) (L1 = 1,3,5-tris(4-pyridylsulfanylmethyl)-2,4,6-trimethylbenzene) were synthesized and structurally characterized by single-crystal x-ray diffraction method. In compound 1 , the coordination environment of Cd(II) ion is distorted octahedral bonded to three nitrogen donors from three L1 ligands located in a facial-position, two nitrogen donors from NCS− and one water molecule. The L1 acts as a bridge ligand with tris-monodentate coordination mode in a cis-cis-cis structural conformation, connecting the Cd(II) to form a two-dimensional (2D) zigzag-like layered metal-organic frameworks. Adjacent 2D layers are then arranged orderly in an ABAB manner to complete its three-dimensional (3D) supramolecular architecture. In compound 2 , the coordination environment of Zn(II) ion is distorted tetrahedral bonded to two nitrogen donors from two L1 ligands and two nitrogen donors from two NCS− ligands. The L1 acts as a bridge ligand with bis-monodentate coordination mode in a cis-cis-cis structural conformation, connecting the Zn(II) ions to form a one-dimensional (1D) zigzag-like polymeric chain. Adjacent chains are arranged orderly in an alternate ABAB manner to generate a 2D framework and then further arranged in an AAA manner to complete its 3D supramolecular architecture. The structural characterization as well as thermal-stability and solvents de-/ad-sorption behavior of 1 and 2 are studied and discussed in details. 相似文献
3.
Stacey M. Frumm Zi Peng Fan Kenneth N. Ross Jeremy R. Duvall Supriya Gupta Lynn VerPlank Byung-Chul Suh Edward Holson Florence F. Wagner William B. Smith Ronald M. Paranal Christopher F. Bassil Jun Qi Giovanni Roti Andrew L. Kung James E. Bradner Nicola Tolliday Kimberly Stegmaier 《Chemistry & biology》2013,20(5):713-725
4.
Yang‐Chu Lin Kung‐Lung Cheng Woan‐Shiow Tzeng Chih‐Lin Su Long‐Je Lee Ling‐Yung Wang 《Liquid crystals》2013,40(3):289-293
A series of N,N‐disubstituted‐4‐[(4‐aminophenyl)diazenyl]benzylidene‐4′‐alkylanilines (azo dyes) were synthesized from the reaction of the corresponding benzaldehyde with alkylanilines. These azo dyes exhibit nematic and SmC phases on heating. Their order parameter, photo‐stability and miscibility were studied by investigation of a representative sample. 相似文献
5.
Dhananjaya Patra Mohan Ramesh Duryodhan Sahu Harihara Padhy Chih‐Wei Chu Kung‐Hwa Wei Hong‐Cheu Lin 《Journal of polymer science. Part A, Polymer chemistry》2012,50(5):967-975
A conjugated main‐chain copolymer ( PBT ) consisting of bithiazole, dithieno[3,2‐b:2′,3′‐d]pyrroles (DTP), and pendent melamine units was synthesized by Stille polymerization, which can be hydrogen‐bonded (H‐bonded) with proper molar amounts of bi‐functional π‐conjugated crosslinker F (i.e., two uracil motifs covalently attached to a fluorene core through triple bonds symmetrically) to develop a novel supramolecular polymer network ( PBT/F ). The effects of multiple H‐bonds on light harvesting capabilities, HOMO levels, and photovoltaic properties of polymer PBT and H‐bonded polymer network PBT/F are investigated. The formation of supramolecular polymer network ( PBT/F ) between PBT and F was confirmed by FTIR and XRD measurements. Because of the stronger light absorption, lower HOMO level, and higher crystallinity of H‐bonded polymer network PBT/F , the solar cell device containing PBT/F showed better photovoltaic properties than that containing polymer PBT . The preliminary results show that the solar cell device containing 1:1 weight ratio of PBT/F and [6,6]‐phenyl C71 butyric acid methyl ester (PC71BM) offers the best power conversion efficiency (PCE) value of 0.86% with a short‐circuit current density (Jsc) of 4.97 mA/cm2, an open circuit voltage (Voc) of 0.55 V, and a fill factor (FF) of 31.5%. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
6.
Cheng‐Hua Lee Meng‐Rong Tsai Yen‐Tzu Chang Prof. Dr. Long‐Li Lai Dr. Kuang‐Lieh Lu Dr. Kung‐Lung Cheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(32):10573-10579
Three unconventional dendrimers that contained rigid NH? triazine linkages and peripheral tert‐butyl moieties were prepared by using a convergent approach and characterized by 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. Based on a thermogravimetric analysis study, these dendrimers were observed to display thermal stability at about 300 °C. The NH? triazine moiety, which possessed protonated and proton‐free nitrogen sites (like the imidazole unit), displayed the capture of polarizable CO2 molecules through hydrogen‐bond and/or dipole–quadrupole interactions. In addition, the adsorption of various amounts of CO2 and N2 at different pressures suggests that the dendritic pores, which arise from the stacking of the middle co‐planar and rim protuberant dendrimers, G n ‐N~N‐G n (n=1–3), either swell or shrink at high pressure, thus indicating that these dendrimers may have a breathing ability. 相似文献
7.
Seongsin M.Kim William Baughman David S.Wilbert Lee Butler Michael Bolus Soner Balci Patrick Kung 《中国光学快报(英文版)》2011,(11):46-49
We demonstrate two distinct emerging terahertz (THz) biomedical imaging techniques.One is based on the use of a new single frequency THz quantum cascade laser and the other is based on broadband THz time domain spectrocopy.The first method is employed to derive a metastasis lung tissue imaging at 3.7 THz with clear contrast between cancerous and healthy areas.The second approach is used to study an osseous tissue under several imaging modalities and achieve full THz spectroscopic imaging based on the freque... 相似文献
8.
Chih-Chieh LoChun-Chao Huang Chien-Min LiuChih Chen Chang-Yang KuoHong-Ji Lin Yuan-Chieh Tseng 《Journal of magnetism and magnetic materials》2011,323(15):1950-1953
Ni and Ni-NiO core-shell nano-arrays were fabricated by means of electroless deposition, where the latter was covered by a NiO shell of ∼10 nm by annealing the former at 350 °C for 30 min in an atmospheric condition. HRTEM showed that the NiO shell was developed at the expense of Ni at the array's surface. Ferromagnetic ordering of the Ni-NiO arrays was found to be suppressed compared with those of the less oxidized reference Ni arrays. This is attributed to the screening effect of the NiO shell, and weak ferromagnetism of inner Ni arrays resulted from the development of the NiO. X-ray absorption spectrum reveals that the reference Ni is partially oxidized. Also, X-ray magnetic circular dichroism suggests that the magnetic suppression of the Ni-NiO arrays is associated with a reduced spin moment. 相似文献
9.
Arnab Bagchi Yu‐Hsuan Huang Z. F. Xu P. Raghunath Yuan T. Lee Chi‐Kung Ni M. C. Lin Yuan‐Pern Lee 《化学:亚洲杂志》2011,6(11):2961-2976
The photodissociation of gaseous benzaldehyde (C6H5CHO) at 193, 248, and 266 nm using multimass ion imaging and step‐scan time‐resolved Fourier‐transform infrared emission techniques is investigated. We also characterize the potential energies with the CCSD(T)/6‐311+G(3df,2p) method and predict the branching ratios for various channels of dissociation. Upon photolysis at 248 and 266 nm, two major channels for formation of HCO and CO, with relative branching of 0.37:0.63 and 0.20:0.80, respectively, are observed. The C6H5+HCO channel has two components with large and small recoil velocities; the rapid component with average translational energy of approximately 25 kJ mol?1 dominates. The C6H6+CO channel has a similar distribution of translational energy for these two components. IR emission from internally excited C6H5CHO, ν3 (v=1) of HCO, and levels v≤2, J≤43 of CO are observed; the latter has an average rotational energy of approximately 13 kJ mol?1 and vibrational energy of approximately 6 kJ mol?1. Upon photolysis at 193 nm, similar distributions of energy are observed, except that the C6H5+HCO channel becomes the only major channel with a branching ratio of 0.82±0.10 and an increased proportion of the slow component; IR emission from levels ν1 (v=1) and ν3 (v=1 and 2) of HCO and v≤2, J≤43 of CO are observed; the latter has an average energy similar to that observed in photolysis at 248 nm. The observed product yields at different dissociation energies are compared to statistical‐theory predicted results based on the computed singlet and triplet potential‐energy surfaces. 相似文献
10.
Yi‐Chin Chen Sheng‐Cih Huang Dr. Yu‐Kuo Wang Dr. Yuan‐Ting Liu Prof. Dr. Tung‐Kung Wu Prof. Dr. Teng‐Ming Chen 《化学:亚洲杂志》2013,8(11):2652-2659
In this study, surface‐functionalized, branched polyethylenimine (BPEI)‐modified YVO4:Bi3+,Eu3+ nanocrystals (NCs) were successfully synthesized by a simple, rapid, solvent‐free hydrothermal method. The BPEI‐coated YVO4:Bi3+,Eu3+ NCs with high crystallinity show broad‐band excitation in the λ=250 to 400 nm near‐ultraviolet (NUV) region and exhibit a sharp‐line emission band centered at λ=619 nm under excitation at λ=350 nm. The surface amino groups contributed by the capping agent, BPEI, not only improve the dispersibility and water/buffer stability of the BPEI‐coated YVO4:Bi3+,Eu3+ NCs, but also provide a capability for specifically targeted biomolecule conjugation. Folic acid (FA) and epidermal growth factor (EGF) were further attached to the BPEI‐coated YVO4:Bi3+,Eu3+ NCs and exhibited effective positioning of fluorescent NCs toward the targeted folate receptor overexpressed in HeLa cells or EGFR overexpressed in A431 cells with low cytotoxicity. These results demonstrate that the ligand‐functionalized, BPEI‐coated YVO4:Bi3+, Eu3+ NCs show great potential as a new‐generation biological luminescent bioprobe for bioimaging applications. Moreover, the unique luminescence properties of BPEI‐coated YVO4:Bi3+,Eu3+ NCs show potential to combine with a UVA photosensitizing drug to produce both detective and therapeutic effects for human skin cancer therapy. 相似文献