pressure silica phase (which they denoted SBAD) with space group Pnc2 from molecular dynamics (MD) simulations. However, we noticed that a simple cell transformation for the reported structural data of the SBAD phase results in a structure that is virtually the same as the well known α-PbO2 type SiO2 structure with space group Pbcn, as previously described by Matsui and Kawamura (1987) and Mats...

The anode material is one of the determining factors for success electrowinning process. This study aims to coat graphite substrate with β-PbO2 produce an inert graphite/β-PbO2 composite low cost and good quality. synthesis expected be used as composites processes. deposition layer was prepared on surface by electrodeposition process using a sulfuric acid electrolyte. effect electrolyte concent...

Lead dioxide has been used for over a century in the lead-acid battery. Many fundamental questions concerning PbO2 remain unanswered, principally: (i) is the bulk material a metal or a semiconductor, and (ii) what is the source of the high levels of conductivity? We calculate the electronic structure and defect physics of PbO2, using a hybrid density functional, and show that it is an n-type se...

The PbO2 electrodes were preservative and chemically stable but had the problem of poor electrocatalytic oxidation activity instability. In this research, Pb/PbO2 with good stability prepared via a novel combined method thermal electrochemical oxidation, which was different form electrodeposition coating method. Combined results analyzed by SEM, metallographic microscope, XRD, steady-state pola...

The electrochemical oxidation of the digested effluent from anaerobic digestion of dairy manure was investigated in this study. The digested effluent sample containing with suspended solids was pretreated by filtration for the electrochemical experiment. The influence of direct anodic oxidation and indirect oxidation was evaluated through the use of dimensionally stable anode (DSA) and Ti/PbO2 ...

The cyclic voltammetry of red PbO, -PbO2, -PbO2 and BaPbO3 was studied with two different types of electrodes in acidic and alkaline media. In one case, microcrystalline particles of lead oxides were mechanically immobilized on the surface of paraffin-impregnated graphite rod electrodes (PIGE), while in the other case, lead oxides were added to a paste of graphite and silicone oil. The overall ...

This work compares two electrode materials used to mineralize phenol contained in waste waters. Two disks covered with either boron doped diamond (BDD) or PbO2 were used as anodes in a one compartment flow cell under the same hydrodynamic conditions. Efficiencies of galvanostatic electrolyses are compared on the basis of measurements of Total Organic Carbon (TOC) and Chemical Oxygen Demand (COD...

X-ray in situ studies in electrically and laser-heated diamond anvil cells (DACs) at pressures over 80 GPa and temperatures above 2500 K were used to determine stable silica phase at extreme conditions. We demonstrate that so far unidenti®ed phases obtained on the compression of a-cristobalite, new dense silica polymorph in the Martian Shergotty meteorite, and controversial post-stishovite phas...