Search results for "Oxide"
showing 10 items of 6424 documents
Design and Characterization of Effective Ag, Pt and AgPt Nanoparticles to H2O2 Electrosensing from Scrapped Printed Electrodes
2019
The use of disposable screen-printed electrodes (SPEs) has extraordinarily grown in the last years. In this paper, conductive inks from scrapped SPEs were removed by acid leaching, providing high value feedstocks suitable for the electrochemical deposition of Ag, Pt and Ag core-Pt shell-like bimetallic (AgPt) nanoparticles, onto screen-printed carbon electrodes (ML@SPCEs, M = Ag, Pt or AgPt, L = metal nanoparticles from leaching solutions). ML@SPCEs were characterized by scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The results were compared to those obtained when metal nanoparticles were synthesised using standard solutions of metal salts (MS@…
Low-temperature thermal and plasma-enhanced atomic layer deposition of metal oxide thin films
2017
Atomic layer deposition (ALD) is a method for thin film fabrication with atomic level precision. This thesis focuses on low-temperature thermal and plasma- enhanced ALD and presents results on thin film growth by these techniques with examples of common ALD materials: Al2O3, ZnO and TiO2. As an example of limitations of the thermal ALD the nucleation and growth of Al2O3 and ZnO films on different grades of poly(methyl methacrylate) (PMMA) are presented, showing that the initiation of the growth is strongly dependent on both the deposited material and the substrate. A potential application of the ALD ZnO films in polymer surface functionalization is demonstrated by changing in the surface wettab…
Carbon Monoxide Activation by a Molecular Aluminium Imide: C−O Bond Cleavage and C−C Bond Formation
2020
Anionic molecular imide complexes of aluminium are accessible via a rational synthetic approach involving the reactions of organo azides with a potassium aluminyl reagent. In the case of K 2 [( NON )Al(NDipp)] 2 ( NON = 4,5‐bis(2,6‐di iso propylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethyl‐xanthene; Dipp = 2,6‐di iso propylphenyl) structural characterization by X‐ray crystallography reveals a short Al‐N distance, which is thought to be due primarily to the low coordinate nature of the nitrogen centre. The Al‐N unit is highly polar, and capable of the activation of relatively inert chemical bonds, such as those found in dihydrogen and carbon monoxide. In the case of CO, uptake of two molecules of …
Trapping and Reactivity of a Molecular Aluminium Oxide Ion
2019
Aluminium oxides constitute an important class of inorganic compound that are widely exploited in the chemical industry as catalysts and catalyst supports. Due to the tendency for such systems to aggregate via Al‐O‐Al bridges, the synthesis of well‐defined, soluble, molecular models for these materials is challenging. Here we show that reactions of the potassium aluminyl complex K 2 [( NON )Al] 2 ( NON = 4,5‐bis(2,6‐diiso‐propylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene) with CO 2 , PhNCO and N 2 O all proceed via a common aluminium oxide intermediate. This highly reactive species can be trapped by coordination of a THF molecule as the anionic oxide complex [( NON )AlO(THF)] ‐ , which …
CCDC 1943794: Experimental Crystal Structure Determination
2020
Related Article: F. Sabbaghi, A. As'habi, A. Saneei, M. Pourayoubi, A.A. Abdul Salam, M. Nečas, M. Dušek, M. Kučeráková, S. Acharya|2021|Acta Crystallogr.,Sect.C:Cryst.Struct.Chem.|77|68|doi:10.1107/S2053229620016502
Soil carbon in Mediterranean ecosystems and related management problems
2011
Interfacial Engineering in Vacuum-Deposited Perovskite Solar Cells for Improved Performance and Space Stability
2021
Perovskite solar cells are an emerging technology that is evolving rapidly, with power conversion efficiency values that compete with traditional materials such as silicon. In this type of solar cells the photons are absorbed in the perovskite and the charges are extracted using transport materials. By sandwiching the perovskite between a material with and excess of negative (N) or positive (P) charge, one can fabricate a P-i-N or N-i-P structure depending on the deposition order of the materials. Perovskite solar cells have several advantages, mainly the possibility of being very thin thanks to the high absorption coefficient of the perovskite and the wide range of deposition techniques, c…
Density of States evaluation of Molybdenum Oxide for c-Si solar cell
Silicon-based heterojunction technology (HJT) is one of the most promising candidates for high performance and low cost solar cells with world-record efficiency close to 27% in IBC architecture. The HJT exploits the excellent passivation properties of hydrogenated amorphous silicon (a-Si:H); although, the use of doped a-Si:H has drawbacks such as parasitic absorption and low-thermal budget to cope with back-end metallization. Replacing the p-type a-Si:H with molybdenum oxide (MoOx) is a viable alternative. Optimizing this hole-selective layer is needed; however information on the defect density of states (DOS), linked to oxygen vacancies is still lacking.
Ti Alloyed α-Ga2O3: Route towards Wide Band Gap Engineering
2020
The suitability of Ti as a band gap modifier for &alpha
Tailoring of the solid state properties of Al-Nb mixed oxides: A photoelectrochemical study
2013
Al-Nb containing mixed oxides were grown by anodizing sputter-deposited Al-Nb alloys of different compositions. A photoelectrochemical investigation was carried out in order to estimate the band gap, flat band potential, and conductivity type of these oxides as a function of their composition. The dependence of the band gap on the composition of mixed sp-d metal oxides has been rationalized by using a semiempirical correlation between the difference of electronegativity and band gap of oxides proposed in the literature some years ago and recently tested for regular d-d metal mixed oxides. The band gap increase observed as a function of Al content into the oxides seems mainly depending on th…