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Copper germanate (CuGeO 3 ) nanowires are used as the modified materials of glassy carbon electrode to investigate the electrochemical behavior of ascorbic acid. The results show that CuGeO 3 nanowire modified glassy carbon electrode exhibits good performance for the electrochemical detection of ascorbic acid in neutral solution. The intensities of two anodic peaks vary linearly with the concentration of ascorbic acid in the range of 0.01-5 mM and the detection limit is 24 μM and 8.6 μM, respectively at a signal-tonoise ratio of 3, which makes it possible to sensitive detection of ascorbic acid using the CuGeO 3 nanowire modified glassy carbon electrode. The CuGeO 3 nanowire modified electrode exhibits good reproducibility and stability. The good analytical performance makes that the CuGeO 3 nanowires can be used as the electrode modified materials for a wide range of potential application for detecting ascorbic acid.Ascorbic acid (AA, vitamin C) is a kind of important micronutrient and biomicromolecule with many physiological roles. 1, 2 Ascorbic acid is also a powerful antioxidant present in food, beverages and used as a marker chemical in evaluating product quality. 3 Furthermore, great interest has been devoted to ascorbic acid in the cosmetic industry for the production of antiaging treatments. It can protect skin against UVA-induced photoinsult and stimulate collagen and procollagen synthesis as well as human fibolast proliferation. 4, 5 As a result, developing convenient, rapid and facile method for detecting ascorbic acid has been the subject of considerable interest for food, chemistry industry, pharmaceutical quality and safety. [6][7][8][9][10][11][12] Electrochemical method has been used to detect ascorbic acid directly owing to the excellent sensitivity, rapid response, low cost and good convenience. The accurate determination of the concentration is of considerable importance, but the reliable sensing of the ascorbic acid using conventional carbon electrodes has been hindered by the large over-potentials required and electrode fouling by the oxidation products. 12 Direct amperometric detection of ascorbic acid at common electrodes, such as carbon and transition metals is difficult owing to the electrode fouling. 13,14 The amperometric determination of ascorbic acid is based on its electrochemical oxidation process. At bare platinum or glassy carbon electrodes, the reaction proceeds at the potential above +500 mV. However, at chemically modified electrodes (CMEs), the necessary overpotential is lowered substantially. 15 The noble metals, 10 C 60 film, 16 carbon nanotube composite films, 17-20 covalently modified polymers and transition metal compound-based cheap catalysts 21-23 have been employed for the detection of ascorbic acid in the presence of other interferents. Therefore, it is of great significance that a reliable electroanalytical technique might offer greater selectivity, time efficiency and reproducibility than existing methods, such as high-performance liquid chromatography, 24 capillary...

LiFePO4 (lithium iron phosphate (LFP)) is a promising cathode material due to its environmental friendliness, high cycling performance, and safety characteristics. On the basis of these advantages, many efforts have been devoted to increasing specific capacity and high-rate capacity to satisfy the requirement for next-generation batteries with higher energy density. However, the improvement of LFP capacity is mainly affected by dynamic factors such as low Li-ion diffusion coefficient and poor electrical conductivity. The electrical conductivity and the diffusion of lithium ions can be enhanced by using novel strategies such as surface modification, particle size reduction, and lattice substitution (doping), all of which lead to improved electrochemical performance. In addition, cathode prelithiation additives have been proved to be quite effective in improving initial capacity for full cell application. The aim of this review paper is to summarize the strategies of capacity enhancement, to discuss the effect of the cathode prelithiation additives on specific capacity, and to analyze how the features of LFP (including its structure and phase transformation reaction) influence electrochemical properties. Based on this literature data analysis, we gain an insight into capacity-enhancement strategies and provide perspectives for the further capacity development of LFP cathode material.