Search

In this work, we propose an in situ hydrolytic method to synthesize SiO2 nanoparticles, which are incorporated in poly(ethylene oxide)-based polymer in the presence of lithium salt with a large anion (lithium bis(oxalate) borate). When evaluated as the solid electrolyte for electrochemical performance in lithium batteries, the as-prepared composite polymer electrolyte (CPE) exhibits an exciting ion conductivity of 1.9 mS/cm at 80 °C. Moreover, the CPE shows a decent Li+ transference number up to 0.69 and wide electrochemical window of 5.05 V at 60 °C. Furthermore, the Li/LiFePO4 cell assembled by the CPE exhibits an impressive capacity of 156.3 mAh/g at 60 °C under 0.05 C (1 C=160 mA/g). Considering the aspects mentioned above, the prepared CPE has the potential to be applied in practical high-temperature batteries with a long-term service life. More importantly, the synthetic strategy is favorable for enhancing both physical and electrochemical performance for solid electrolyte and may provide a new strategy for study and fabrication of lithium batteries. [ABSTRACT FROM AUTHOR]

As a promising cathode material of sodium-ion battery, P2-type Na 2/3 Ni 1/3 Mn 2/3 O 2 (NNMO) possesses a theoretically high capacity and working voltage to realize high energy storage density. However, it still suffers from poor cycling stability mainly incurred by the undesirable P2-O2 phase transition. Herein, the electrochemically active Fe 3+ ions are introduced into the lattice of NNMO, forming Na 2/3 Ni 1/3 Mn 2/3- x Fe x O 2 ( x = 0, 1/24, 1/12, 1/8, 1/6) to effectively stabilize the P2-type crystalline structure. In such Fe-substituted materials, both Ni 2+ /Ni 4+ and Fe 3+ /Fe 4+ couples take part in the redox reactions, and the P2-O2 phase transition is well restrained during cycling, as verified by ex situ X-ray diffraction. As a result, the optimized Na 2/3 Ni 1/3 Mn 7/12 Fe 1/12 O 2 (1/12-NNMF) has a long-term cycling stability with the fading rate of 0.05% per cycle over 300 cycles at 5 C. Furthermore, the 1/12-NNMF delivers excellent rate capabilities (65 mA h g -1 at 25 C) and superior low-temperature performance (the capacity retention of 94% at -25 °C after 80 cycles) owing to the enhanced Na diffusion upon Fe doping, which is deduced by the studies of electrode kinetics. More significantly, the 1/12-NNMF also displays remarkable sodium-ion full-cell properties when merged with an LS-Sb@G anode, thus implying the possibility of their practical application.

MnO is a promising high-capacity anode material for lithium-ion batteries (LIBs), but pristine material suffers short cycle life and poor rate capability, thus hindering the practical application. In this work, a new type of porous MnO microballs stringed with N-doped porous carbon (3DHB-MnO@NC) with a well-connected hierarchical three-dimensional network structure was prepared by the facile self-template method. The 3DHB-MnO@NC electrode can effectively promote the ion/electron transfer and buffer the large volume change of electrode during the electrochemical reaction. As the anode for LIBs, the 3DHB-MnO@NC possesses outstanding cycling performance (1247.7 mA h g -1 after 90 cycles at 200 mA g -1 ) and good rate capabilities (949.6 mA h g -1 after 450 cycles at 1000 mA g -1 ). The facile self-template method of the prepared 3DHB-MnO@NC composite paves a new way for practical applications of MnO in high performance LIBs., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Polymetallic complexes with interesting multifunctions have attracted extensive investigation. Synthesized through the use of different cobalt salt anions and solvents, five complexes, namely [Co II 4 Co III 3 (H 2 L) 3 Cl 5 (MeOH)] (1), [Co II 4 Co III 3 (H 2 L) 3 (CH 3 COO) 4 (HCOO)⋅H 2 O] n (2), [Co II 4 Co III 3 (H 2 L) 3 (HCOO) 4 (NO 3 )⋅2H 2 O] n (3), [Co II 4 Co III 3 (H 2 L) 3 (bda)(CH 3 COO) 4 ⋅2H 2 O] n (4), and [Co II 4 Co III 3 (H 2 L) 3 (ipa)(HCOO) 3 (dmf)⋅H 2 O] n (5) (H 6 L=bis-tris propane; BDA=biphenyl-4,4'-dicarboxylic acid; IPA=isophthalic acid; DMF=N,N-dimethylformamide), based on the heptanuclear {Co II 4 Co III 3 } cluster with structures from 0D to 3D metal-organic frameworks (MOFs) have been solvothermally synthesized. Compound 1 is the first 0D heptanuclear cluster based on H 6 L. Compound 2 crystallizes in the chiral space group P2 1 2 1 2 1 and consists of a 1D chiral helical chain. Complex 3 exhibits a 3D network structure. Compound 4 possesses a 1D zigzag-like chain structure. Finally, compound 5 was obtained as a 3D microporous structure. Compounds 1, 3, and 4 display dominant ferrimagnetic interactions whereas compounds 2 and 5 exhibit antiferromagnetic interactions. Moreover, the Co 3 O 4 prepared by calcining compound 2 presents a reversible capacity of 1122.9 mA h g -1 at 0.2 A g -1 after 100 cycles and an excellent rate capability, which suggests that coordination compounds with a 1D chain structure are outstanding precursors for preparing anode materials for lithium ion batteries., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Marcasite (m-FeS 2 ) exhibits higher electronic conductivity than that of pyrite (p-FeS 2 ) because of its lower semiconducting gap (0.4 vs 0.7 eV). Meanwhile, as demonstrates stronger Fe-S bonds and less S-S interactions, the m-FeS 2 seems to be a better choice for electrode materials compared to p-FeS 2 . However, the m-FeS 2 has been seldom studied due to its sophisticated synthetic methods until now. Herein, a hierarchical m-FeS 2 and carbon nanofibers composite (m-FeS 2 /CNFs) with grape-cluster structure was designed and successfully prepared by a straightforward hydrothermal method. When evaluated as an electrode material for lithium ion batteries, the m-FeS 2 /CNFs exhibited superior lithium storage properties with a high reversible capacity of 1399.5 mAh g -1 after 100 cycles at 100 mA g -1 and good rate capability of 782.2 mAh g -1 up to 10 A g -1 . The Li-storage mechanism for the lithiation/delithiation processes of m-FeS 2 /CNFs was systematically investigated by ex situ powder X-ray diffraction patterns and scanning electron microscopy. Interestingly, the hierarchical m-FeS 2 microspheres assembled by small FeS 2 nanoparticles in the m-FeS 2 /CNFs composite converted into a mimosa with leaves open shape during Li + insertion process and vice versa. Accordingly, a "CNFs accelerated decrystallization-recrystallization" mechanism was proposed to explain such morphology variations and the decent electrochemical performance of m-FeS 2 /CNFs.

Aim: To investigate the association between serum human epidermal growth factor receptor 2 (HER2) extracellular domain (ECD) and tissue HER2 status, and the prognostic value of serum HER2 ECD in patients with gastric cancer., Methods: A total of 239 patients with gastric cancer were enrolled from December 2012 to June 2013. Serum HER2 ECD was determined by chemiluminescent assay, and tissue HER2 status was evaluated by immunohistochemistry and fluorescence in situ hybridization assay. A receiver operating characteristic (ROC) curve was plotted to identify the optimal cut-off value for serum HER2 ECD assay for predicting survival in gastric cancer patients., Results: Serum HER2 ECD was significantly correlated with tissue HER2 status ( P < 0.001), tumor size ( P < 0.001), and intestinal type of gastric cancer ( P = 0.021). Serum HER2 ECD levels differed significantly between patients with HER2-positive tissue expression and those with HER2-negative tissue expression. ROC analysis yielded an area under the curve value of 0.79 (95%CI: 0.71-0.87, P < 0.001), with a sensitivity and specificity of 0.54 (95%CI: 0.37-0.70) and 0.93 (95%CI: 0.88-0.96), respectively. With a cut-off value of 24.75 ng/mL, high serum HER2 ECD had a negative impact on overall survival of the patients (HR: 1.93, 95%CI: 1.32-4.38, P = 0.006)., Conclusion: Serum HER2 ECD could be a highly specific surrogate biomarker for tissue HER2 status in gastric cancer. Optimal cut-off criteria for predicting survival should be established., Competing Interests: Conflict-of-interest statement: All the authors have no conflict of interest.