Effect of rare earth Eu on anti-passivation of metal oxide anode coating

The anti passivation effect of metal oxide anode coating doped with rare earth element Eu was discussed. The morphology and the composition distribution of the metal oxide coating anode before and after electrolysis were studied by SEM and EDX analyses. The results show that the erosion of the electrolyte at the defects is the main cause for the failure of the coating. The erosion rate of the electrolyte is anisotropic. In area with high density of defects, the erosion rate is very fast and the failure of the coating is very quick. Moreover, the life time of the coating is prolonged by the doping of Eu. [

Formation of Ultrafine Metal Particles and Metal Oxide Precursor on Anodized Al by Electrolysis Deposition

Nickel was deposited by ac electrolysis deposition in the pores of the porous oxide film of Al produced by anodizing in phosphoric acid. Ultrafine rod-shaped Ni particles were formed in the pores. At the same time a film of Ni oxide precursor was developed on the surface of the porous oxide film. The Ni particles and the Ni oxide precursor were examined by SEM, TEM and X-ray diffraction. The thickness of the barrier layer of the porous oxide film was thin and it attributed to the formation of the metal particles, while the formation of the oxide precursor was associated with the surface pits which were developed in the pretreatment of Al.

EFFECT OF SnO_2 ADDITION ON THE SERVICE LIFE AND ELECTROCHEMICAL PROPERTIES OF Ti/IrO_2,+Ta_2O_5 ANODES IN PHENOLSULFONIC ACID SOLUTION

Service life of two different oxide anodes in phenolsulfonic acid (PSA) solution was investigated by accelerated electrolysis. The durability of Ti/IrO_2+Ta_2 O_5 anode increased by the addition of SnO_2 in the mixed oxides. The degradation mechanisms of Ti/IrO_2+ Ta_2 O_5 and Ti/IrO_2 +Ta_2 O_5 +SnO+2 anodes were different. It was shown from the observation of scanning electron microscopy (SEM) and the electrochcmical measurement that, the deactivation of Ti/IrO_2 + Ta_2 O_5 anode was due to the build-up of an organic film on surface. The growth of the covered film on surface was restricted by addition of SnO_2, which resulted in increasing of the service life of anodes. The over-potential for oxygen evolution on Ti/IrO_2 +Ta_2 O_5 electrode increased after doping SnO_2, and the intermediate products of PSA building-up on the surface was much more rapidly oxidized. Meanwhile, a certain part of the surface oxide deposit entered into the solution leading to loss of oxides, which resulted in degradation of Ti/IroO_2 + Ta_2 O_5 anode containing SnO_2 component.

Nanostructured transition metal oxides as advanced anodes for lithium-ion batteries

The exploration for post-carbon electrode ma- terials for lithium-ion batteries has been a crucial way to satisfy the ever-growing demands for better performance with higher energy/power densities, enhanced safety, and longer cycle life. Transition metal oxides have recently re- ceived a great deal of attention as very promising anode materials due to their high theoretical capacity, good safety, eco-benignity, and huge abundance. The present work re- views the latest advances in developing novel transition metal oxides, including FeeO3, Fe3O4, CO3O4, CoO, NiO, MnO, Mn203, Mn3O4, MnO2, MOO3, Cr2O3, Nb2O5, and some binary oxides such as NiCO2O4, ZnCO2O4, MnCO2O4 and CoMn2O4. Nanostructuring and hybrid strategies ap- plicable to transition metal oxides are summarized and analyzed. Furthermore, the impacts of binder choice and heat treatment on electrochemical performance are discussed.