Conductometric semiconducting metal oxide gas sensors have been widely used and investigated in the detection of gases. Investigations have indicated that the gas sensing process is strongly related to surface reactions, so one of the important parameters of gas sensors, the sensitivity of the metal oxide based materials, will change with the factors influencing the surface reactions, such as c...

Conventional Metal Oxide gas sensors commonly used for sensing inflammable hydrocarbon gases and other toxic gases suffer from the two limitations, viz. (a) their relatively high operating temperature (≥300° c) and (b) large power dissipation (≥1 Watt). In this paper we establish that use of nanocrystalline metal oxide in place of polycrystalline metal oxide lead to large increase of free surfa...

We propose an unexplored class of absorbing materials for high-efficiency solar cells: heterostructures of transition-metal oxides. In particular, LaVO(3) grown on SrTiO(3) has a direct band gap ∼1.1  eV in the optimal range as well as an internal potential gradient, which can greatly help to separate the photogenerated electron-hole pairs. Furthermore, oxide heterostructures afford the flexibi...

In the Mott insulating phase of the transition metal oxides, the effective orbital-orbital interaction is directional both in orbital space and in real space. We discuss a classical realization of directional coupling in two dimensions. Despite extensive degeneracy of the ground state, the model exhibits partial orbital ordering in the form of directional ordering of fluctuations at low tempera...

Charge transport in nanoparticle-based materials underlies many emerging energy-conversion technologies, yet assessing the impact of nanometre-scale structure on charge transport across micrometre-scale distances remains a challenge. Here we develop an approach for correlating the spatial distribution of crystalline and current-carrying domains in entire nanoparticle aggregates. We apply this a...

In this paper, the effect of nanocatalytic metal-organic framework based on copper metal and bis-tetrazolamine (CuBTA) ligand functionalized with cobalt (II) oxide nanoparticles on the thermal decomposition behavior of ammonium perchlorate (AP), using differential survey calorimetry (DSC) has been reviewed. First, the metal-organic framework (CuBTA) was synthesized from the raw materials of cop...

morphology of surface oxide film formed during pouring of molten magnesium alloy has been investigated. due to surface turbulence during casting, the oxide film necessarily makes folded cause in a dry surface to dry surface mode creating a double oxide film with the volume of air that can be encapsulated between folds of the film and this led to make gas bubbles or shrinkage cavities form. thes...

The interactions of two-dimensional vanadium oxide and molybdenum oxide overlayers with the surface hydroxyls of an alumina support were examined with 'H MAS NMR spectroscopy. The measurements demonstrated that these surface metal oxide overlayers are homogeneously distributed over the alumina surface and essentially titrate all the accessible surface hydroxyls at monolayer coverage. The invest...

The catalytic oxidation of sulfur dioxide to sulfur trioxide over several binary (MxOy/TiO2) and ternary (V2O5/MXOY/TiO2) supported metal oxide catalysts was systematically investigated. The supported metal oxide components were essentially 100% dispersed as surface metal oxide species, as confirmed by Raman spectroscopy characterization. The sulfur dioxide oxidation turnover frequencies of the...

Several important sediment geochemical factors (particle size, contact time, artificial sediment composition, acid volatile sulfide, and pure inorganic particles coated or uncoated with humic acid) were examined for their influences on the assimilation of Cd, Cr, and Zn in the marine clam Ruditapes philippinarum. Metal desorption and phase speciation were concurrently measured for these particl...