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A chelating-agent-assisted Na2/3Fe1/2Mn1/2O2 material is studied as a cathode for sodium-ion batteries. The addition of NH4OH results in the formation of a homogeneous powder with a lower resistance and larger carbon content on the cathode surface. The formation of a thin and stable solid-electrolyte interface layer leads to its enhanced electrochemical performance.

The valence band structures and ionization energies of pentacene layers grown on poly (3,4-ethylenedioxythiophene) polymerized with poly (4-styrenesulfonate) (PEDOT:PSS) and Au electrodes were characterized using in situ ultraviolet photoemission spectroscopy. The pentacene layers grown on Au films consist of amorphous phase and round oval grains regardless of the pentacene deposition temperature, whereas the pentacene deposited on PEDOT:PSS films showed highly distinctive ordered structures depending on the deposition conditions. The pentacene layer (thickness: 30 nm) grown on PEDOT:PSS at room temperature (RT) showed a highly crystalline thin film phase (001) and typical terrace-like structure, but that grown on PEDOT:PSS at 100◦C consists of a weakly oriented thin film/bulk mixed phase with a disordered grain structure. However, irrespective of the molecular ordering structure, the pentacene layers grown on PEDOT:PSS films showed nearly the same hole-injection barriers (0.40 ∼ 0.45 eV) at both interface (10 nm) and bulk regions (30 nm). On the basis of the correlation between the molecular ordering and device characteristics, we conclude that the carrier transport at pentacene/electrode interface relies more on the hole-injection barrier than on the ordering of the pentacene layer grown on the electrode. © 2013 The Electrochemical Society. [DOI: 10.1149/2.038308jes] All rights reserved.

The electrochemical lithiation–delithiation reaction was examined for LiMnPO 4 in which different cations were substituted for part of Mn. The X-ray diffraction analysis indicated that LiMnPO 4 is tolerant, to some extent, to substitution of Mg 2+ , Ca 2+ and Zr 4+ . The substitution of Mg 2+ and/or Zr 4+ led to an increased reversible capacity and a reduced polarization, whereas Ca 2+ substitution had a detrimental effect on the electrochemical properties. The potential transient analysis showed that LiMn 0.88 Mg 0.1 Zr 0.02 PO 4 has higher lithium diffusivities than pure LiMnPO 4 , indicating facilitated diffusion kinetics in the substituted material. Upon the first charge–discharge cycle, LiMn 0.88 Mg 0.1 Zr 0.02 PO 4 suffered less irreversible capacity loss when compared with LiMnPO 4 , and smaller amounts of electrolyte salt-based species were detected on the electrode surface of LiMn 0.88 Mg 0.1 Zr 0.02 PO 4 .

The damage of an amorphous Ga 2 O 3 -In 2 O 3 -ZnO (a-GIZO) thin-film transistor (TFT) due to dry etching was removed by wet-cleaning treatment and characterized in terms of electrical performance. The damaged channel layer by dry etch had lower chemical bonding energy than that of the as-deposited layer due to physical bombardment. It seems to be oxygen deficient and to have a reduction of metal cation. The existence of a damaged layer in the a-GIZO TFT tends to significantly deteriorate threshold voltage, subthreshold swing, and off-current. With the wet-cleaning treatment, however, the damaged layer was successfully removed, thereby revealing significantly recovered electrical performances. X-ray photoelectron spectroscopy, Auger electron spectroscopy, and transmission electron spectroscopy analysis support the evidences such as channel-layer composition, chemical bonding structure, and cross structure.