Atomic Layer Deposition of ZnO on Mesoporous Silica: Insights into Growth Behavior of ZnO via In-Situ Thermogravimetric Analysis

ZnO is a remarkable material with many applications in electronics and catalysis. Atomic layer deposition (ALD) of ZnO on flat substrates is an industrially applied and well-known process. Various studies describe the growth of ZnO layers on flat substrates. However, the growth characteristics and reaction mechanisms of atomic layer deposition of ZnO on mesoporous powders have not been well studied. This study investigates the ZnO ALD process based on diethylzinc (DEZn) and water with silica powder as substrate. In-situ thermogravimetric analysis gives direct access to the growth rates and reaction mechanisms of this process. Ex-situ analytics, e.g., N2 sorption analysis, XRD, XRF, HRTEM, and STEM-EDX mapping, confirm deposition of homogenous and thin films of ZnO on SiO2. In summary, this study offers new insights into the fundamentals of an ALD process on high surface area powders.

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Ultralow Loading (Single‐Atom and Clusters) of the Pt Catalyst by Atomic Layer Deposition Using Dimethyl ((3,4‐η) N , N ‐dimethyl‐3‐butene‐1‐amine‐ N ) Platinum (DDAP) on the High‐Surface‐Area Substrate for Hydrogen Evolution Reaction

Advanced Materials Interfaces ◽

10.1002/admi.202001508 ◽

2020 ◽

pp. 2001508

Author(s):

Rahul Ramesh ◽

Seungmin Han ◽

Dip K. Nandi ◽

Sandesh Y. Sawant ◽

Deok Hyun Kim ◽

...

Keyword(s):

Atomic Layer Deposition ◽

Surface Area ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Single Atom ◽

Pt Catalyst ◽

Layer Deposition

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Conformal ZnO coatings on high surface area silica gel using atomic layer deposition

Thin Solid Films ◽

10.1016/j.tsf.2007.11.044 ◽

2008 ◽

Vol 516 (18) ◽

pp. 6158-6166 ◽

Cited By ~ 67

Author(s):

J.A. Libera ◽

J.W. Elam ◽

M.J. Pellin

Keyword(s):

Atomic Layer Deposition ◽

Surface Area ◽

Silica Gel ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Layer Deposition

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High-Surface Area Ceria-Zirconia Films Prepared by Atomic Layer Deposition

Catalysis Letters ◽

10.1007/s10562-017-2053-1 ◽

2017 ◽

Vol 147 (6) ◽

pp. 1464-1470 ◽

Cited By ~ 6

Author(s):

Tzia Ming Onn ◽

Sheng Dai ◽

Jiayao Chen ◽

Xiaoqing Pan ◽

George W. Graham ◽

...

Keyword(s):

Atomic Layer Deposition ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Layer Deposition ◽

Zirconia Films

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Boron Nitride as a Novel Support for Highly Stable Palladium Nanocatalysts by Atomic Layer Deposition

Nanomaterials ◽

10.3390/nano8100849 ◽

2018 ◽

Vol 8 (10) ◽

pp. 849 ◽

Cited By ~ 13

Author(s):

Matthieu Weber ◽

Cassandre Lamboux ◽

Bruno Navarra ◽

Philippe Miele ◽

Sandrine Zanna ◽

...

Keyword(s):

Boron Nitride ◽

Atomic Layer Deposition ◽

Photoelectron Spectroscopy ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Average Diameter ◽

Transmission Electron Microscopy Analysis ◽

Layer Deposition ◽

Palladium Nanocatalysts

The ability to prepare controllable nanocatalysts is of great interest for many chemical industries. Atomic layer deposition (ALD) is a vapor phase technique enabling the synthesis of conformal thin films and nanoparticles (NPs) on high surface area supports and has become an attractive new route to tailor supported metallic NPs. Virtually all the studies reported, focused on Pd NPs deposited on carbon and oxide surfaces. It is, however, important to focus on emerging catalyst supports such as boron nitride materials, which apart from possessing high thermal and chemical stability, also hold great promises for nanocatalysis applications. Herein, the synthesis of Pd NPs on boron nitride (BN) film substrates is demonstrated entirely by ALD for the first time. X-ray photoelectron spectroscopy indicated that stoichiometric BN formed as the main phase, with a small amount of BNxOy, and that the Pd particles synthesized were metallic. Using extensive transmission electron microscopy analysis, we study the evolution of the highly dispersed NPs as a function of the number of ALD cycles, and the thermal stability of the ALD-prepared Pd/BN catalysts up to 750 °C. The growth and coalescence mechanisms observed are discussed and compared with Pd NPs grown on other surfaces. The results show that the nanostructures of the BN/Pd NPs were relatively stable up to 500 °C. Consequent merging has been observed when annealing the samples at 750 °C, as the NPs’ average diameter increased from 8.3 ± 1.2 nm to 31 ± 4 nm. The results presented open up exciting new opportunities in the field of catalysis.

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Atomic Layer Deposition of GdCoO3 and Gd0.9Ca0.1CoO3

Materials ◽

10.3390/ma13010024 ◽

2019 ◽

Vol 13 (1) ◽

pp. 24

Author(s):

Marion Duparc ◽

Henrik Hovde Sønsteby ◽

Ola Nilsen ◽

Anja Olafsen Sjåstad ◽

Helmer Fjellvåg

Keyword(s):

Thin Films ◽

Aspect Ratio ◽

Atomic Layer Deposition ◽

High Aspect Ratio ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Oxidation Catalysis ◽

Post Annealing ◽

Layer Deposition

Thin films of the catalytically interesting ternary and quaternary perovskites GdCoO3 and Gd0.9Ca0.1CoO3 are fabricated by atomic layer deposition using metal β-diketonates and ozone as precursors. The resulting thin films are amorphous as deposited and become single-oriented crystalline on LaAlO3(100) and YAlO3(100/010) after post-annealing at 650 °C in air. The crystal orientations of the films are tunable by choice and the orientation of the substrate, mitigated through the interface via solid face epitaxy upon annealing. The films exhibit no sign of Co2+. Additionally, high-aspect-ratio Si(100) substrates were used to document the suitability of the developed process for the preparation of coatings on more complex, high-surface-area structures. We believe that coatings of GdCoO3 and Gd1−xCaxCoO3 may find applications within oxidation catalysis.

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In Situ Microgravimetric Study of Ion Exchanges in the Ternary Cu-In-S System Prepared by Atomic Layer Deposition

Materials ◽

10.3390/ma13030645 ◽

2020 ◽

Vol 13 (3) ◽

pp. 645

Author(s):

Harold Le Tulzo ◽

Nathanaelle Schneider ◽

Frédérique Donsanti

Keyword(s):

Atomic Layer Deposition ◽

Reaction Mechanisms ◽

Atomic Layer ◽

Side Reactions ◽

Chemical Surface ◽

Copper Indium Disulfide ◽

Layer Deposition ◽

Copper Indium ◽

Gas Phase Ion

Reaction mechanisms during the growth of multinary compounds by atomic layer deposition can be complex, especially for sulfide materials. For instance, the deposition of copper indium disulfide (CuInS2) shows a non-direct correlation between the cycle ratio, the growth per cycle of each binary growth cycles, i.e., CuxS and In2S3, and the film composition. This evidences side reactions that compete with the direct Atomic Layer Deposition (ALD) growth reactions and makes the deposition of large films very challenging. To develop a robust upscalable recipe, it is essential to understand the chemical surface reactions. In this study, reaction mechanisms in the Cu-In-S ternary system were investigated in-situ by using a quartz crystal microbalance system to monitor mass variations. Pure binary indium sulfide (In2S3) and copper sulfide (CuxS) thin film depositions on Al2O3 substrate were first studied. Then, precursors were transported to react on CuxS and In2S3 substrates. In this paper, gas-phase ion exchanges are discussed based on the recorded mass variations. A cation exchange between the copper precursor and the In2S3 is highlighted, and a solution to reduce it by controlling the thickness deposited for each stack of binary materials during the CuInS2 deposition is finally proposed.

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Smart Pd Catalyst with Improved Thermal Stability Supported on High-Surface-Area LaFeO3Prepared by Atomic Layer Deposition

Journal of the American Chemical Society ◽

10.1021/jacs.7b12900 ◽

2018 ◽

Vol 140 (14) ◽

pp. 4841-4848 ◽

Cited By ~ 56

Author(s):

Tzia Ming Onn ◽

Matteo Monai ◽

Sheng Dai ◽

Emiliano Fonda ◽

Tiziano Montini ◽

...

Keyword(s):

Thermal Stability ◽

Atomic Layer Deposition ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Pd Catalyst ◽

Layer Deposition

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High Surface Area VOx/TiO2/SBA-15 Model Catalysts for Ammonia SCR Prepared by Atomic Layer Deposition

Catalysts ◽

10.3390/catal10121386 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1386

Author(s):

Jun Shen ◽

Christian Hess

Keyword(s):

Atomic Layer Deposition ◽

Lewis Acid ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Acid Sites ◽

Lewis Acid Sites ◽

X Ray ◽

Nox Conversion ◽

Layer Deposition

The mode of operation of titania-supported vanadia (VOx) catalysts for NOx abatement using ammonia selective catalytic reduction (NH3-SCR) is still vigorously debated. We introduce a new high surface area VOx/TiO2/SBA-15 model catalyst system based on mesoporous silica SBA-15 making use of atomic layer deposition (ALD) for controlled synthesis of titania and vanadia multilayers. The bulk and surface structure is characterized by X-ray diffraction (XRD), UV-vis and Raman spectroscopy, as well as X-ray photoelectron spectroscopy (XPS), revealing the presence of dispersed surface VOx species on amorphous TiO2 domains on SBA-15, forming hybrid Si–O–V and Ti–O–V linkages. Temperature-dependent analysis of the ammonia SCR catalytic activity reveals NOx conversion levels of up to ~60%. In situ and operando diffuse reflection IR Fourier transform (DRIFT) spectroscopy shows N–Hstretching modes, representing adsorbed ammonia and -NH2 and -NH intermediate structures on Bronsted and Lewis acid sites. Partial Lewis acid sites with adjacent redox sites are proposed as the active sites and desorption of product molecules as the rate-determining step at low temperature. The high NOx conversion is attributed to the presence of highly dispersed VOx species and the moderate acidity of VOx supported on TiO2/SBA-15.

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