ALD Applied to Conformal Coating of Nanoporous γ-Alumina: Spinel Formation and Luminescence Induced by Europium Doping

2019 ◽  
Vol 41 (2) ◽  
pp. 123-130 ◽  
Author(s):  
Erwan Rauwel ◽  
Ola Nilsen ◽  
Augustinas Galeckas ◽  
John Walmsley ◽  
Erling Rytter ◽  
...  
Keyword(s):  
Conformal Coating ◽  
Spinel Formation ◽  
Europium Doping

ALD Applied to Conformal Coating of Nanoporous γ-Alumina: Spinel Formation and Luminescence Induced by Europium Doping

2012 ◽  
Vol 159 (4) ◽  
pp. P45-P49 ◽  
Author(s):  
E. Rauwel ◽  
A. Galeckas ◽  
P. Rauwel ◽  
O. Nilsen ◽  
J. C. Walmsley ◽  
...  
Keyword(s):  
Conformal Coating ◽  
Spinel Formation ◽  
Europium Doping

scholarly journals Films and Materials Derived from Aminomalononitrile

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 82
Author(s):  
Helmut Thissen ◽  
Richard A. Evans ◽  
Vincent Ball
Keyword(s):  
Surface Chemistry ◽  
Surface Functionalization ◽  
State Of The Art ◽  
Chemical Reactivity ◽  
The State ◽  
Deposition Kinetics ◽  
Conformal Coating ◽  
Early Atmosphere ◽  
Living Organisms ◽  
Hypothetical Structure

In recent years major advances in surface chemistry and surface functionalization have been performed through the development, most often inspired by living organisms, of versatile methodologies. Among those, the contact of substrates with aminomalononitrile (AMN) containing solutions at pH = 8.5 allows a conformal coating to be deposited on the surface of all known classes of material. Since AMN is a molecule probably formed in the early atmosphere of our planet and since HCN-based compounds have been detected on many comets and Titan (Saturn’s largest moon) it is likely that such molecules will open a large avenue in surface functionalization mostly for bio-applications. This mini review describes the state of the art of AMN-based coatings from their deposition kinetics, composition, chemical reactivity, hypothetical structure to their first applications as biomaterials. Finally, the AMN-based versatile coatings are compared to other kinds of versatile coating based on catecholamines and polyphenols.

Improving photocatalysis and magnetic recyclability in Bi 5 Fe 0.95 Co 0.05 Ti 3 O 15 via europium doping

2016 ◽  
Vol 686 ◽  
pp. 306-311 ◽  
Author(s):  
Zhu Zhu ◽  
Xiaoning Li ◽  
Wen Gu ◽  
Jianlin Wang ◽  
Haoliang Huang ◽  
...  
Keyword(s):  
Europium Doping ◽  
O 15

scholarly journals Optimal n-Type Al-Doped ZnO Overlayers for Charge Transport Enhancement in p-Type Cu2O Photocathodes

Micromachines ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 338
Author(s):  
Hak Hyeon Lee ◽  
Dong Su Kim ◽  
Ji Hoon Choi ◽  
Young Been Kim ◽  
Sung Hyeon Jung ◽  
...  
Keyword(s):  
Charge Transport ◽  
Atomic Layer ◽  
Absorption Efficiency ◽  
Open Circuit ◽  
Band Alignment ◽  
Conformal Coating ◽  
Layer Deposition ◽  
Layer Stacking ◽  
Doped Zno ◽  
P Type

An effective strategy for improving the charge transport efficiency of p-type Cu2O photocathodes is the use of counter n-type semiconductors with a proper band alignment, preferably using Al-doped ZnO (AZO). Atomic layer deposition (ALD)-prepared AZO films show an increase in the built-in potential at the Cu2O/AZO interface as well as an excellent conformal coating with a thin thickness on irregular Cu2O. Considering the thin thickness of the AZO overlayers, it is expected that the composition of the Al and the layer stacking sequence in the ALD process will significantly influence the charge transport behavior and the photoelectrochemical (PEC) performance. We designed various stacking orders of AZO overlayers where the stacking layers consisted of Al2O3 (or Al) and ZnO using the atomically controlled ALD process. Al doping in ZnO results in a wide bandgap and does not degrade the absorption efficiency of Cu2O. The best PEC performance was obtained for the sample with an AZO overlayer containing conductive Al layers in the bottom and top regions. The Cu2O/AZO/TiO2/Pt photoelectrode with this overlayer exhibits an open circuit potential of 0.63 V and maintains a high cathodic photocurrent value of approximately −3.2 mA cm−2 at 0 VRHE for over 100 min.

Thermodynamical Calculations and Experimental Confirmation about the Mg-Al-Spinel Reaction Path in the Sol-Gel-Process

2006 ◽  
Vol 317-318 ◽  
pp. 135-138 ◽  
Author(s):  
Wilfried Wunderlich ◽  
Krupathi Vishista ◽  
Francis D. Gnanam ◽  
Daniel Doni Jayaseelan
Keyword(s):  
Thermal Analysis ◽  
Reaction Path ◽  
Sol Gel ◽  
Chemical Processing ◽  
Aluminium Isopropoxide ◽  
Spinel Formation ◽  
Sol Gel Process ◽  
Wet Chemical ◽  
Enthalpy Data ◽  
Good Agreement

The aim of this research is, to clarify which route the sol-gel-process is taking in the case of a Al-Mg-spinel slurry, in particular, whether the hydrolysis reaction or the spinel formation is faster and which of the intermediate hydroxide phases Al(OH)3, and Mg(OH)2, or MgO and Al2O3 or MgAl2O4H2O are formed during the spinel formation. The spinel-alloy was produced using the polymeric route during wet chemical processing. Aluminium-isopropoxide was hydrolyzed in order to form the boehmite-sol and then the same amount of magnesia was added and mixed. This sol precipitated as boehmite (AlOOH) and brucite (Mg(OH)2) after ageing for 12h as confirmed by differential thermal analysis (DTA), and differential thermal gravity (DTG) measurements. After that, the powders were subsequently annealed at 900oC for 3h in air and observed by TEM. Calculations using thermodynamic enthalpy data are in good agreement with the experiments and can be used to predict reaction paths in other system as well.

Spinel Formation from Magnesium Aluminium Double Alkoxides

1986 ◽  
Vol 73 ◽  
Author(s):  
Kenneth Jones ◽  
Thomas J. Davies ◽  
Harold G. Emblem ◽  
Peter Parkes
Keyword(s):  
Nmr Spectroscopy ◽  
General Formula ◽  
Metal Atom ◽  
Vacuum Distillation ◽  
Viscosity Measurements ◽  
Spinel Formation ◽  
Bonding Phase ◽  
Xrd Studies ◽  
Aluminium Alkoxide

ABSTRACTDouble alkoxides of the general formula Mg[Al(OR)4]2 where R is iso-Pr or sec-Bu were prepared by reacting aluminium and magnesium metals together with the alcohol ROH and purified by vacuum distillation. They were characterised by IR, proton and 27Al NMR spectroscopy and MW determination. A magnesium aluminium double alkoxide was also prepared by treating the commercially available aluminium alkoxide ‘Aliso B’ [a mixed aluminium (iso-propoxide)(sec-butoxide)] with magnesium and iso-propanol. Treatment of magnesium aluminium double alkoxides with water and an alkanolamine (preferably triethanolamine) gives a rigid coherent gel. Viscosity measurements and 27Al NMR spectroscopy suggest that the double alkoxide does not break down to its constituents during hydrolysis. The air-dried gel was shown by XRD to convert quantitatively to spinel on firing to 1500°C. The resistance of the double alkoxide moiety to hydrolysis explains the ease of conversion to spinel on firing. The gel has been used to bind alumina and magnesia grain. Gels suitable for binding refractory grain were obtained only when the alkanolamine content corresponded to one alkanolamine group per metal atom. Electron micrographic and XRD studies showed that in fired refractory pieces, the bonding phase was spinel.

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