Aluminum Oxide Nanoparticle Films Deposited from a Nonthermal Plasma: Synthesis, Characterization, and Crystallization

Abstract

Aluminum oxide, both in amorphous and crystalline forms, is a widely used inorganic ceramic material because of its chemical and structural properties. In this work, we synthesized amorphous aluminum oxide nanoparticles using a capacitively coupled nonthermal plasma utilizing trimethylaluminum and oxygen as precursors and studied their crystallization and phase transformation behavior through postsynthetic annealing. The use of two reactor geometries resulted in amorphous aluminum oxide nanoparticles with similar compositions but different sizes. Size tuning of these nanoparticles was achieved by varying the reactor pressure to produce amorphous aluminum oxide nanoparticles ranging from 6 to 22 nm. During postsynthetic annealing, powder samples of amorphous nanoparticles began to crystallize at 800 °C, forming crystalline θ and γ phase alumina. Their phase transformation behavior was found to be size-dependent in that powders of small 6 nm amorphous particles transformed to form phase-pure α-Al 2 O 3 at 1100 °C, while powders of large 11 nm particles remained in the θ and γ phases. This phenomenon is attributed to the fast rate of densification and neck formation in small amorphous aluminum oxide particles.

New Construction of Functionalized CuO/Al2O3 Nanocomposite-Based Polymeric Sensor for Potentiometric Estimation of Naltrexone Hydrochloride in Commercial Formulations

“…Moreover, more attention has been focused on the perspective of copper oxide in various aspects such as antibacterial agents [12], catalysis [13], food packaging [14], sensors [15] and medicine [16]. Recently, there has been a growing awareness of the development of aluminium oxide nanoparticles (Al 2 O 3 NPs) which have a high specific surface area with extraordinary optical, catalytic, thermodynamic stability properties for progressive engineering and industrial applications [17][18][19]. Few studies reported the use of CuO/Al 2 O 3 in sensing applications such as Khan et al [20] studied the electrochemical oxidation of ammonia over copper oxide impregnated γ-Al 2 O 3 nanocatalysts.…”

Synthesis of bimetallic aluminum–iron oxide nanorice, nanocubes and nanospheres

“…7C1). The peaks marked with a star (*) in 43,56,57 The effect of annealing at 1100 1C for 4 h on the bimetallic Al 2 O 3 -Fe 2 O 3 nanoparticles was also characterized using TEM (Fig. S5, ESI †).…”

“…These phase transitions from amorphous AlO x to α-Al 2 O 3 and α-Al 2 O 3 to α-Al 2 O 3 have been addressed previously. 43,56,57…”

Treatment of Waste Water from Li-ion Batteries Cathode Material Production: Selection of adsorbents

“…The thickness of this layer can be increased through an anodizing process. Some alloys, such as aluminum bronze, take advantage of this property by adding aluminum to the alloy to increase its corrosion resistance [34].…”