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941.
Meng-Meng Zhao Lin Zhou Ping-Ping Shi Xuan Zheng Xiao-Gang Chen Ji-Xing Gao Lei He Prof. Dr. Qiong Ye Prof. Dr. Cai-Ming Liu Prof. Dr. Da-Wei Fu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(25):6447-6454
Organic–inorganic hybrid perovskite-type multiferroics have attracted considerable research interest owing to their fundamental scientific significance and promising technological applications in sensors and multiple-state memories. The recent achievements with divalent metal dicyanamide compounds revealed such malleable frameworks as a unique platform for developing novel functional materials. Herein, two 3D organic–inorganic hybrid perovskites [Et3P(CH2)2F][Mn(dca)3] ( 1 ) and [Et3P(CH2)2Cl][Mn(dca)3] ( 2 ) (dca=dicyanamide, N(CN)2−) are presented. Accompanying the sequential phase transitions, they display a broad range of intriguing physical properties, including above room temperature ferroelastic behavior, switchable dielectricity, and low-temperature antiferromagnetic ordering (Tc=2.4 K for both 1 and 2 ). It is also worth noting that the spontaneous strain value of 1 is far beyond that of 2 in the first ferroelastic phase, as a result of the precise halogen substitution. From the point view of molecular design, this work should inspire further exploration of multifunctional molecular materials with desirable properties. 相似文献
942.
Dr. Liangqi Gui Xiaoyun Miao Chengjun Lei Kailin Wang Dr. Wei Zhou Dr. Beibei He Prof. Qing Wang Dr. Ling Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(47):11007-11014
Implementing sustainable energy conversion and storage technologies is highly reliant on crucial oxygen electrocatalysis, such as the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). However, the pursuit of low cost, energetic efficient and robust bifunctional catalysts for OER and ORR remains a great challenge. Herein, the novel Na-ion-deficient Na2−xCoP2O7 catalysts are proposed to efficiently electrocatalyze OER and ORR in alkaline solution. The engineering of Na-ion deficiency can tune the electronic structure of Co, and thus tailor the intrinsically electrocatalytic performance. Among the sodium cobalt phosphate catalysts, the Na1.95CoP2O7 (NCPO5) catalyst exhibits the lowest ΔE (EJ10,OER−EJ−1,ORR) of only 0.86 V, which favorably outperforms most of the reported non-noble metal catalysts. Moreover, the Na-ion deficiency can stabilize the phase structure and morphology of NCPO5 during the OER and ORR processes. This study highlights the Na-ion deficient Na2−xCoP2O7 as a promising class of low-cost, highly active and robust bifunctional catalysts for OER and ORR. 相似文献
943.
Mengci He Prof. Hongyan Shi Peng Wang Prof. Xiudong Sun Prof. Bo Gao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(70):16106-16113
Molybdenum carbide (Mo2C) is a promising noble-metal-free electrocatalyst for the hydrogen evolution reaction (HER), due to its structural and electronic merits, such as high conductivity, metallic band states and wide pH applicability. Here, a simple CVD process was developed for synthesis of a Mo2C on carbon cloth (Mo2C@CC) electrode with carbon cloth as carbon source and MoO3 as the Mo precursor. XRD, Raman, XPS and SEM results of Mo2C@CC with different amounts of MoO3 and growth temperatures suggested a two-step synthetic mechanism, and porous Mo2C nanostructures were obtained on carbon cloth with 50 mg MoO3 at 850 °C (Mo2C-850(50)). With the merits of unique porous nanostructures, a low overpotential of 72 mV at current density of 10 mA cm−2 and a small Tafel slope of 52.8 mV dec−1 was achieved for Mo2C-850(50) in 1.0 m KOH. The dual role of carbon cloth as electrode and carbon source resulted into intimate adhesion of Mo2C on carbon cloth, offering fast electron transfer at the interface. Cyclic voltammetry measurements for 5000 cycles revealed that Mo2C@CC had excellent electrochemical stability. This work provides a novel strategy for synthesizing Mo2C and other efficient carbide electrocatalysts for HER and other applications, such as supercapacitors and lithium-ion batteries. 相似文献
944.
Yu Liang Wen-Xuan Wang Xing Wu Meng Wang Chao-Jun Pu Zheng-Hui Li Tao Feng Juan He Ji-Kai Liu 《Tetrahedron letters》2019,60(28):1838-1840
Panisuffrutin A (1), a highly degraded seco-triterpene derivative, together with the known palbinone, has been isolated from the whole plant Paeonia suffruticosa var. papaveracea (Andr.) Kerner. The structure with absolute configuration of 1 was determined via comprehensive NMR and MS analyses, as well as NMR and ECD calculations. A plausible biosynthetic pathway for 1 was proposed. Compound 1 showed weak cytotoxicity against Hela cancer cell line with an IC50 value of 26.2 μM, while palbinone exhibited a moderate inhibition on NO production with an IC50 of 18.3 μM. 相似文献
945.
946.
Liang Wanjun Liu Zhengqing Li Dan Wu Xiaoping Liu Shaopu He Youqiu 《Mikrochimica acta》2015,182(1-2):297-306
Microchimica Acta - We describe a novel fluorescent bioprobe for the sensitive and selective detection of double-stranded DNA (dsDNA). It consists of quantum dots (Q-dots) whose fluorescence is... 相似文献
947.
948.
Fan Wang Zicheng Zuo Liang Li Kuo Li Feng He Zhongqing Jiang Yuliang Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(42):15152-15157
A two‐dimensional (2D) carbon nanofilm with uniform artificial nanopores is an ideal material to ultimately suppress the fuel permeation in the proton exchange membrane fuel cells. Graphdiyne has great mechanical strength, high dimensional stability, and controllable nanopores, and has good prospects to play this crucial role. It is found that graphdiyne nanofilm with amino groups and natural nanopores can be easily prepared with high integrity. The aminated graphdiyne has good compatibility with the Nafion matrix owing to the acid–base interaction between them. The excellent comprehensive properties of graphdiyne in selectivity, dimensional stability, and integrity effectively improve the power performance and stability of fuel cells at wide temperature. Our results can be developed into a universal method that can easily realize the selective separation of ions and small molecules, and open a new way for the emerging applications in green energy. 相似文献
949.
950.
Haoyue Shen Chun Kou Min He Han Yang Kuan Liu 《Journal of polymer science. Part A, Polymer chemistry》2014,52(6):739-751
Two novel anionic conjugated copolyelectrolytes PSDPPPV and PSDPPPE were synthesized via Heck/Sonogashira coupling reactions and characterized by FT‐IR, 1H NMR, UV‐vis, and PL spectroscopy. The two polymers are respectively constituted of 2,5‐diethoxy‐1,4‐phenyleneethynylene (DPV) and 2,5‐diethoxy‐1,4‐phenyleneethynylene (DPE) with 1,4‐diketo‐2,5‐bis(4‐sulfonylbutyl)‐3,6‐diphenylpyrrolo[3,4‐c]pyrrole (SDPP) which is a novel water soluble diketopyrrolopyrrole derivative. PSDPPPV and PSDPPPE show broad absorption band in visible region and they exhibit strong fluorescence quenching in aqueous solution. The fluorescence of their aqueous solutions can be enhanced in the presence of cationic surfactant or polymer nonionic surfactant. Fluorescence enhancement by introduction of polyvinylpyrrolidone (PVP) shows linear response. This result provides a controllable method to increase fluorescence intensity of dipyrrolopyrrole‐based conjugate polyelectrolytes in aqueous phase. The optical properties suggested that PSDPPPV and PSDPPPE which are negatively charged conjugated polymers can assemble with positively charged photovoltaic materials to form ionic photoactive layer. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 739–751 相似文献