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51.
Ling-Bin Kong Mao-Cheng Liu Jun-Wei Lang Min Liu Yong-Chun Luo Long Kang 《Journal of Solid State Electrochemistry》2011,15(3):571-577
A new porous cobalt hydroxide film has been successfully electrodeposited on nickel foam from 0.1?M cobalt nitrate electrolyte at ?1.0?V vs. SCE without adding any surfactant. The microstructure and surface morphology of prepared cobalt hydroxide films were physically characterized by X-ray diffraction analysis and scanning electron microscopy. The results indicate that an interlaced network structure was obtained. The effects of electrodeposition time, deposition potential, and different substrates on the specific capacitance and microstructure of prepared porous ??-Co(OH)2 thin film were systematically studied. The results indicate that the film deposited on nickel foam at ?1.0?V has excellent electrochemical properties. A maximum specific capacitance of 1473?F?g?1 could be achieved at a current density of 2?A?g?1. 相似文献
52.
A multiwalled carbon nanotubes (MWNT) modified glassy carbon electrode (GCE) coated with poly(orthanilic acid) (PABS) film
(PABS–MWNT/GCE) has been fabricated and used for simultaneous determination of dopamine (DA) and uric acid (UA) in the presence
of ascorbic acid (AA) by differential pulse voltammetry (DPV). Scanning electron microscopy, Fourier transform infrared spectra,
and electrochemical techniques have been used to characterize the surface morphology of the PABS–MWNT composite film and the
polymerization of ABS on electrode surface. In comparison with the bare GCE and the MWNT-modified GCE, the PABS–MWNT composite
film-modified GCE, which combines the advantages of MWNT and the self-doped PABS, exhibits good selectivity and sensitivity
for the simultaneous and selective determination of UA and DA in the presence of AA. Due to the different electrochemical
responses of AA, DA, and UA, PABS–MWNT/GCE can resolve the overlapped oxidation peak of DA and UA into two well-defined voltammetric
peaks with enhanced current responses using both cyclic voltammetry (CV) and DPV. The peak potential separations between DA
and UA are 170 mV using CV and 160 mV using DPV, respectively, which are large enough for the selective and simultaneous determination
of these species. In the presence of 0.5 mM AA, the DPV peak currents are linearly dependent on the concentration of UA and
DA in the range of 6–55 and 9–48 μM with correlation coefficients of 0.997 and 0.993, respectively. The detection limits (S/N = 3) for detecting UA and DA are 0.44 and 0.21 μM, respectively. The PABS–MWNT/GCE shows good reproducibility and stability
and has been used for the simultaneous determination of DA and UA in the presence of AA in samples with satisfactory results. 相似文献
53.
Tongyong Yang Kening Sun Zhengyu Lei Naiqing Zhang Ye Lang 《Journal of Solid State Electrochemistry》2011,15(2):391-397
LiNi0.5Mn1.5O4 cathode materials were successfully prepared by sol–gel method with two different Li sources. The effect of both lithium
acetate and lithium hydroxide on physical and electrochemical performances of LiNi0.5Mn1.5O4 was investigated by scanning electron microscopy, Fourier transform infrared, X-ray diffraction, and electrochemical method.
The structure of both samples is confirmed as typical cubic spinel with Fd3m space group, whichever lithium salt is adopted. The grain size of LiNi0.5Mn1.5O4 powder and its electrochemical behaviors are strongly affected by Li sources. For the samples prepared with lithium acetate,
more spinel nucleation should form during the precalcination process, which was stimulated by the heat released from the combustion
of extra organic acetate group. Therefore, the particle size of the obtained powder presents smaller average and wider distribution,
which facilitates the initial discharge capacity and deteriorates the cycling performance. More seriously, there exists cation
replacement of Li sites by transition metal elements, which causes channel block for Li ion transference and deteriorates
the rate capability. The compound obtained with lithium hydroxide exhibits better electrochemical responses in terms of both
cycling and rate properties due to higher crystallinity, moderate particle size, narrow size distribution and lower transition
cation substitute content. 相似文献
54.
Samat Abdurehman Dr. Lang Liu Prof. Dianzeng Jia Jianping Hu Dr. Jixi Guo Prof. Xiaolin Xie 《Chemphyschem》2011,12(12):2338-2344
Two novel photochromic compounds, 1,3‐diphenyl‐4‐benzal‐5‐hydroxypyrazole 4‐phenylsemicarbazone ( 1 a ) and 1,3‐diphenyl‐4‐(4‐nitrobenzal)‐5‐hydroxypyrazole 4‐phenylsemicarbazone ( 2 a ), are synthesized and characterized by elemental analysis, mass spectrometry, FTIR spectroscopy, and 1H NMR spectroscopy. Their properties, including photochromic behavior, fluorescence properties, and thermal bleaching kinetics, are investigated. The results show that the two compounds exhibit improved photochromic performance in coloration and thermal bleaching rates, excellent photostability, high fatigue resistance, and reversible fluorescence switching properties in the solid state in comparison to reported pyrazolone thiosemicarbazones. The thermal bleaching process obeys first‐order kinetics. Bleaching of powders at 130 °C is completed within 90 s for 1 b (the colored isomer of 1 a ) and 150 s for 2 b (the colored isomer of 2 a ). The activation energy for the thermal bleaching process is determined to be 69 and 95 kJ mol?1, with frequency factors of 9.5×107 and 9.4×1010 s?1 for 1 b and 2 b , respectively. 相似文献
55.
Andrea Preuß Marcus Korb Tobias Rüffer Jörn Bankwitz Colin Georgi Alexander Jakob Stefan E. Schulz Heinrich Lang 《无机化学与普通化学杂志》2020,646(13):670-680
The template synthesis of ethylenediamine ( 1 ) with 2-acetylcyclopentanone ( 2 ) and [Cu(OAc)2 · H2O] ( 5 ) produced [Cu(1-(2-cC5H6(O))C(Me)NCH2)2)] ( 6 ) in 82 % yield. Reaction of 5 with bis(benzoylacetone)diethylenetriamine ( 7 , = L H)[1] gave [Cu(μ-OAc)( L )(H2O)]2 ( 8 ). The solid-state structures of 6 and 8 were determined confirming that 8 possesses intra- and intermolecular hydrogen bonds resulting in a dimer formation. The thermal behavior of 6 – 8 was studied by TG and TG-MS. Under oxygen CuO was formed, whereas under Ar Cu/Cu2O ( 6 ) or Cu ( 8 ) was obtained. Complex 6 was used as CVD precursor for Cu and Cu-oxide deposition (substrate temp., 400–500 °C, N2, 60 mL · min–1; O2, 60 mL · min–1; pressure, 0.87–1.5 mbar). The as-obtained deposits show separated particles of different appearance at the substrate surface as evidenced by SEM. Non-volatile 8 was applied as spin-coating precursor for Cu and CuO formation [conc. 0.25 mol · L–1; volume 0.2 mL; 3000 rpm; depos. time 2 min; heating rate 50 K · min–1; holding time 60 min (Ar), 120 min (air) at 800 °C]. The samples on silicon consist of granulated particles (Ar) or are non-dense with a grainy topography (air). EDX and XPS measurements confirmed the formation of Cu (Ar) or CuO (O2) with up to 13 mol-% C impurity. 相似文献
56.
Sebastian Scharf Eduard Kovalski Tobias Rüffer Alexander Hildebrandt Heinrich Lang 《无机化学与普通化学杂志》2020,646(22):1820-1833
The synthesis of [Ti6O4(OiPr)8(O2CPh)8] ( 3 ) and [RuCl(N≡CR)5][RuCl4(N≡CR)2] ( 4a , R = Me; 4b , R = Ph), [Ru(N≡CPh)6][RuCl4(N≡CPh)2] ( 5 ) and [H3O][RuCl4(N≡CMe)2] ( 7a ) is discussed. Crystallization of 5 from CH2Cl2 gave trans-[RuCl2(N≡CPh)4] ( 6 ). The solid-state structures of 3 , 4a , b , 5 , 6 and 7a are reported. Complex 4b forms a 3D network, while 6 displays a 2D structure, due to π-interactions between the benzonitrile ligands. The (spectro)electrochemical behavior of 4a , b and 6 was studied at 25 and –72 °C and the results thereof are compared with [NEt4][RuCl4(N≡CMe)2] ( 7b ) and [RuCl(N≡CPh)5][PF6] ( 8 ). The electrochemical response of the cation and the anion in 4a , b are independent from each other. [RuCl(N≡CR)5]+ possesses one reversible RuII/RuIII process. However, [RuCl4(N≡CMe)2]– was shown to be prone to ligand exchange and disproportionation upon formation of either a RuIV and RuII species at 25 °C, while at –72 °C the rapid conversion of the electrochemically formed species is hindered. In situ IR and UV/Vis/NIR studies confirmed the respective disproportionation reaction products of the aforementioned oxidation and reduction, respectively. 相似文献
57.
以3-甲基-4-对溴苯基-5-(2-吡啶基)-1,2,4-三氮唑作为配体(L),合成了1个新的锰配合物[MnL2(NCS)2],对其进行了红外、电喷雾质谱和单晶结构表征,该配合物属于单斜晶系,空间群P21/n,a=1.6480(2)nm,b=0.90707(13)nm,c=2.1919(3)nm,β=97.454(2)°,V=3.248 8(8)nm3,Z=4,R1=0.043 9。单晶结构表明,锰离子处于1个扭曲的八面体配位环境中,2个硫氰根离子呈顺式配位,每个配体L通过三氮唑上1个氮原子和吡啶上1个氮原子参与配位。 相似文献
58.
Dr. Xi-Sha Zhang Yan-Ying Huang Jing Zhang Dr. Wei Meng Dr. Qian Peng Ruirui Kong Zhenwei Xiao Dr. Jie Liu Miaofei Huang Dr. Yuanping Yi Liangliang Chen Qingrui Fan Dr. Gaobo Lin Dr. Zitong Liu Dr. Guanxin Zhang Dr. Lang Jiang Prof. Dr. Deqing Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3557-3561
Polycyclic aromatic hydrocarbons with hexagons/pentagons or hexagons/heptagons have been intensively investigated in recent years, but those with simultaneous presence of hexagons, pentagons and heptagons remain rare. In this paper, we report dicyclohepta[ijkl,uvwx]rubicene ( DHR ), a non-benzenoid isomer of dibenzo[bc,kl]coronene with two pentagons and two heptagons. We developed an efficient and scalable synthetic method for DHR by using Scholl reaction and dehydrogenation. Crystal structure of DHR shows that the benzenoid rings, two pentagons and two heptagons are coplanar. The bond lengths analysis and the ICSS(1)zz and LOL-π calculations indicate that the incorporation of two formal azulene moieties has an effect on the conjugated structure. The π-electrons of benzenoid and pentagon rings are more delocalized. Cyclic voltammetry studies indicate that DHR shows multiple oxidation and reduction potentials. Interestingly, DHR exhibits unusual S0 to S2 absorption and abnormal anti-Kasha S2 to S0 emission. Moreover, crystals of DHR exhibit semiconducting behaviour with hole mobility up to 0.082 cm2 V−1 s−1. 相似文献
59.
Dou Ma Ping Li Xiangyu Duan Jiazhen Li Pengpeng Shao Dr. Zhongling Lang Lixia Bao Dr. Yuanyuan Zhang Dr. Zhengguo Lin Prof. Dr. Bo Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(10):3933-3937
Metal–organic frameworks (MOFs) with long-term stability and reversible high water uptake properties can be ideal candidates for water harvesting and indoor humidity control. Now, a mesoporous and highly stable MOF, BIT-66 is presented that has indoor humidity control capability and a photocatalytic bacteriostatic effect. BIT-66 (V3(O)3(H2O)(BTB)2), possesses prominent moisture tunability in the range of 45–60 % RH and a water uptake and working capacity of 71 and 55 wt %, respectively, showing good recyclability and excellent performance in water adsorption–desorption cycles. Importantly, this MOF demonstrates a unique photocatalytic bacteriostatic behavior under visible light, which can effectively ameliorate the bacteria and/or mold breeding problem in water adsorbing materials. 相似文献
60.
Wei Zhou Jun-Kang Guo Sheng Shen Jinbo Pan Jie Tang Lang Chen Chak-Tong Au Shuang-Feng Yin 《物理化学学报》2020,36(3):1906048-0
CO_2是最常见的化合物,作为潜在的碳一资源,可用于制备多种高附加值的化学品,如一氧化碳、甲烷、甲醇、甲酸等。传统的热催化转化CO_2方法能耗高,反应条件苛刻。因此,如何在温和条件下高效地将CO_2转化成高附加值的化学品,一直以来是催化领域的研究热点和难点之一。光催化技术反应条件温和、绿色环保。然而,纯光催化反应普遍存在太阳能利用效率有限,光生载流子分离效率低等问题。针对上述问题,在光催化的基础上引入电催化,可以提高载流子的分离效率,在较低的过电位下,实现多电子、质子向CO_2转移,从而提高催化反应效率。总之,光电催化技术可以结合光催化和电催化的优势,提高CO_2催化还原反应效率,为清洁、绿色利用CO_2提供了一种新方法。本文依据光电催化CO_2还原反应基本过程,从光吸收、载流子分离和界面反应等三个角度综述了光电催化反应的基本强化策略,并对未来可能的研究方向进行了展望。 相似文献