Hydrothermal Synthesis and Photocatalytic Property of β-Ga2O3 Nanorods

Abstract

Gallium oxide (Ga2O3) nanorods were facilely prepared by a simple hydrothermal synthesis, and their morphology and photocatalytic property were studied. The gallium oxide hydroxide (GaOOH) nanorods were formed in aqueous growth solution containing gallium nitrate and ammonium hydroxide at 95 °C of growth temperature. Through the calcination treatment at 500 and 1000 °C for 3 h, the GaOOH nanorods were converted into single crystalline α-Ga2O3 and β-Ga2O3 phases. From X-ray diffraction analysis, it could be confirmed that a high crystalline quality of β-Ga2O3 nanorods was achieved by calcinating at 1000 °C. The thermal behavior of the Ga2O3 nanorods was also investigated by differential thermal analysis, and their vibrational bands were identified by Fourier transform infrared spectroscopy. In order to examine the photocatalytic activity of samples, the photodegradation of Rhodamine B solution was observed under UV light irradiation. As a result, the α-Ga2O3 and β-Ga2O3 nanorods exhibited high photodegeneration efficiencies of 62 and 79 %, respectively, for 180 min of UV irradiation time.

Growth and Photocatalytic Properties of Gallium Oxide Films Using Chemical Bath Deposition

“…Metal oxides, such as titanium dioxide, zinc oxide, and gallium oxide (Ga 2 O 3 ), are considered promising for photocatalytic applications due to their excellent physical and chemical properties [7][8][9][10][11]. Among these metal oxides, Ga 2 O 3 , with various polymorphs (α-, β-, γ-, δ-, and ε-) can be synthesized at different temperatures [12,13].…”

Phase junction enhanced photocatalytic activity of Ga2O3 nanorod arrays on flexible glass fiber fabric

“…The separated carriers eventually diffuse to the surface of the sample to participate in the photocatalytic reaction. 4 On the other hand, for Ga 2 O 3 as a photocatalytic degradation material, the performance of the b phase is generally better than that of the a phase, 7,43 which is conrmed in Fig. 4(a) of this research.…”

“…† The decrease of the characteristic peak at 554 nm during illumination suggests RhB decomposition. 1,43 Fig. 4(a) and S2 † reveals the comparison of photocatalytic activities of different Ga 2 O 3 NRAs.…”

“…38 Many methods have been investigated to further improve the photocatalytic activity of Ga 2 O 3 , including morphology controlling, doping, surface modication and semiconductor coupling. [39][40][41][42][43][44] Nitu Syed et al reported a two-step method for the synthesis of porous a-Ga 2 O 3 nanosheets from liquid metal gallium, explaining that the excellent photocatalytic activity of a-Ga 2 O 3 originated from the narrowed bandgap caused by trap states. 1 Han et al revealed that the modication of in situ Ag nanoparticles can effectively improve the photocatalytic property of Ga 2 O 3 for hydrogen evolution.…”

High-Aspect Ratio β-Ga2O3 Nanorods via Hydrothermal Synthesis

“…Like other semiconductors, the low-dimensional properties of β -Ga 2 O 3 have broadened the science of the materials, eventually leading to the promotion of innovative technologies, which have in turn promoted the development of new materials [7,8,9,10]. Numerous studies have been conducted on the synthesis and characterization of one-dimensional (1D) and two-dimensional (2D) β -Ga 2 O 3 [11,12,13] mainly via chemical reaction-based approaches such as hydrolysis, sol–gel methods, electrospinning, and the hydrothermal method [14,15,16,17,18,19,20]. Among these various methods, β -Ga 2 O 3 prepared via the hydrothermal method has been popular due to the resulting high crystallinity [21,22,23,24,25,26].…”