Nanoporous gyroid metal oxides with controlled thickness and composition by atomic layer deposition from block copolymer templates

2016 ◽  
Vol 4 (4) ◽  
pp. 840-849 ◽  
Author(s):  
Wei-Chun Ma ◽  
Wei-Shiang Huang ◽  
Ching-Shun Ku ◽  
Rong-Ming Ho
Keyword(s):  
Mechanical Properties ◽  
Block Copolymer ◽  
Atomic Layer Deposition ◽  
Specific Surface ◽  
Metal Oxides ◽  
Atomic Layer ◽  
High Porosity ◽  
Large Specific Surface Area ◽  
Layer Deposition ◽  
Superior Mechanical Properties

Nanoporous gyroid metal oxides were fabricated with controlled tube thickness and composition by templated atomic layer deposition giving high porosity and large specific surface area as well as superior mechanical properties.

Interface Studies of Metal Oxides Grown Directly on Hybrid Perovskite by Atomic Layer Deposition

2019 ◽  
Author(s):  
Claire Burgess ◽  
Farzad Mardekatani Asl ◽  
Valerio Zardetto ◽  
Herbert Lifka ◽  
Sjoerd Veenstra ◽  
...  
Keyword(s):  
Atomic Layer Deposition ◽  
Metal Oxides ◽  
Atomic Layer ◽  
Hybrid Perovskite ◽  
Layer Deposition

Chemical resistance of thin film materials based on metal oxides grown by atomic layer deposition

2013 ◽  
Vol 542 ◽  
pp. 219-224 ◽  
Author(s):  
Väino Sammelselg ◽  
Ivan Netšipailo ◽  
Aleks Aidla ◽  
Aivar Tarre ◽  
Lauri Aarik ◽  
...  
Keyword(s):  
Thin Film ◽  
Atomic Layer Deposition ◽  
Metal Oxides ◽  
Chemical Resistance ◽  
Atomic Layer ◽  
Layer Deposition

Atomic Layer Deposition for Improved Stability of Catalysts for the Conversion of Biomass to Chemicals and Fuels

2011 ◽  
Vol 1366 ◽  
Author(s):  
Monika K. Wiedmann ◽  
Yomaira J. Pagan-Torres ◽  
Mark H. Tucker ◽  
James A. Dumesic ◽  
T. F. Kuech
Keyword(s):  
Atomic Layer Deposition ◽  
Metal Oxides ◽  
Rate Constant ◽  
Flow Reactor ◽  
Atomic Layer ◽  
Deactivation Rate ◽  
Layer Deposition ◽  
Improved Stability ◽  
Deactivation Rate Constant ◽  
Acid Catalyzed

ABSTRACTAtomic layer deposition (ALD) has been used to coat SBA-15 and functionalized SBA-15 with various metal oxides. Use of SBA-15 coated with 4-10 ALD cycles of titania, alumina, niobia, or zirconia in the acid-catalyzed dehydration of fructose to 5-hydroxymethylfurfural (HMF) resulted in 24-57% conversion, with 0-22% selectivity, at 130 °C with 2 wt % fructose in 4:1 THF:H2O. Propylsulfonic acid functionalized SBA-15 (SBA-15-PrSO3H) had a 25% conversion and 48% selectivity for HMF under the same conditions. SBA-15-PrSO3H was also coated with 2 ALD cycles of titania followed by 8 ALD cycles silica. The deactivation rate constant for SBA-15-PrSO3H was 2.7 x 10-2 h-1 for the dehydration of fructose to HMF in a flow reactor at 130 °C with a feed of 2 wt % fructose in 4:1 THF:H2O. In comparison, the deactivation rate constant for the ALD coated SBA-15-PrSO3H-ALD was 7.9 x 10-3 h-1.

Direct patterning of metal oxides by hard templates and atomic layer deposition

2013 ◽  
Vol 10 (8/9) ◽  
pp. 692 ◽  
Author(s):  
Hyunchul Kim ◽  
Changdeuck Bae ◽  
Hyun Suk Jung ◽  
Jang Sik Lee ◽  
Hyunjung Shin
Keyword(s):  
Atomic Layer Deposition ◽  
Metal Oxides ◽  
Atomic Layer ◽  
Direct Patterning ◽  
Layer Deposition

Circular Double-Patterning Lithography Using a Block Copolymer Template and Atomic Layer Deposition

2018 ◽  
Vol 5 (16) ◽  
pp. 1800054 ◽  
Author(s):  
Zhixin Wan ◽  
Ha Jin Lee ◽  
Hyun Gu Kim ◽  
Gyeong Cheon Jo ◽  
Woon Ik Park ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Atomic Layer Deposition ◽  
Atomic Layer ◽  
Layer Deposition ◽  
Double Patterning

scholarly journals Novel Catalysts for Selective Catalytic Reduction of NOx by NH3 Prepared by Atomic Layer Deposition of V and Ti Oxides on SiO2 Powder

2020 ◽  
Vol 2 (1) ◽  
pp. 33
Author(s):  
Davyd Urbanas ◽  
Pranas Baltrėnas ◽  
Saeed Saedy ◽  
Aristeidis Goulas ◽  
J. Ruud van Ommen
Keyword(s):  
Nitrogen Oxides ◽  
Atomic Layer Deposition ◽  
Specific Surface ◽  
Selective Catalytic Reduction ◽  
Surface Area ◽  
Catalytic Reduction ◽  
Atomic Layer ◽  
Nh3 Scr ◽  
Layer Deposition ◽  
Highly Porous

Based on the 2019 report of the European Environment Agency on Air Quality in Europe nitrogen oxides (NOx) were identified as the most harmful air pollutants in terms of damage to ecosystems. Moreover, in Europe, NO2 is pinpointed as one of the most dangerous pollutants for human health. Anthropogenic emissions of NOx are mainly generated by the combustion of fossil fuels. Nitrogen oxides being emitted into the atmosphere cause environmental problems such as acid rain, acidification of soil, lakes and rivers, eutrophication and photochemical smog. The most effective and widely applicable technology to date for the purification of flue gases from NOx is selective catalytic reduction using ammonia (NH3-SCR de-NOx). Nowadays, one of the most significant research fields in NH3-SCR de-NOx is the application of unconventional reduction methods and the preparation of novel catalysts possessing high specific surface area, uniformity, dispersion of active sites, activity and selectivity. Atomic layer deposition (ALD) is an attractive technique for the deposition of uniformly distributed active catalytic layers, or nanoparticles, on highly porous substrates characterized by a complex structure. For this type of materials, conventional catalyst preparation methods (e.g., impregnation or deposition precipitation) can encounter several limitations. The significant advantage of ALD for the preparation of supported catalysts is that the process can be controlled on the atomic scale, providing the required thickness of an active layer, synthesized with a sub-nm accuracy. Moreover, ALD ensures the formation of catalytic sites from the gas phase, which enhances the possibility of active species being deposited inside pores which are very small in size. In this study, ALD was applied to the preparation of VxOy-based NH3-SCR de-NOx catalysts. Highly porous silica gel powder (63–100 μm) with a specific surface area of up to 450 m2·g−1 was used as a substrate for VxOy/SiO2 with different metal loadings (wt.%). In addition (VxOy+TiO2)/SiO2 catalysts were prepared by applying vanadium (V) tri-i-propoxy oxide (VTIP) and titanium tetrachloride (TiCl4) as precursors with deionized water as the co-reactant. Elemental analysis (ICP-OES) revealed that vanadium loadings of the VxOy/SiO2 catalysts were 0.3, 0.7, 1.1 and 1.60 wt.%, while the loadings in the TiO2-promoted VxOy/SiO2 catalyst were 1.0 and 0.2 wt.% for V and Ti, respectively. The obtained XPS spectra indicated the presence of V2O3 and V2O5 species (V2O5/V2O3 ratio was 1.6 and 6.3 for the as-synthesized and calcined samples respectively). Vanadium(V) oxide is known to be a catalytically active compound for NH3-SCR de-NOx. Additionally, TEM, XRD and N2 adsorption (BET) analyses were conducted to provide a comprehensive characterization of the species size, crystalline phase and porosity of the catalysts prepared.

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