Green synthesis of β-Ga₂O₃ nanoparticles via Cnidoscolus aconitifolius leaf extract and photocatalytic activity for methylene blue degradation

In this research, green synthesis of β-Ga₂O₃ nanoparticles via Cnidoscolus aconitifolius leaf extract in methanol, n-hexane, and water solvent has been successfully performed for the first time. XRD and FTIR results showed that the obtained β-Ga₂O₃ nanoparticles are single phased (monoclinic, C12/m1 space group) with characteristic Ga–O vibration of GaO₄ and GaO₆ complex. UV–Vis DRS result showed that β-Ga₂O₃-M, β-Ga₂O₃-Hx, and β-Ga₂O₃– W nanoparticles were optically active in ultraviolet light region with bandgap value of 4.59 eV, 4.66 eV, and 4.61 eV, respectively. SEM-EDS results showed that morphological shape of β-Ga₂O₃-M, β-Ga₂O₃-Hx, and β-Ga₂O₃–W are irregular shape, rod-like, and microspindle. TEM characterization confirmed SEM results and showed that β-Ga₂O₃-M, β-Ga₂O₃-Hx, and β-Ga₂O₃–W have an average particle size of 38 nm, 885 nm, and 2514 nm. Photocatalytic activity of β-Ga₂O₃-M, β-Ga₂O₃-Hx, and β-Ga₂O₃–W nanoparticles in methylene blue (MB) photodegradation were 92.64%, 20.07%, and 86.70%, respectively. The superior photocatalytic activity of β-Ga₂O₃-M could be attributed to the small nano-sized particles which provide high surface area. This work suggests a facile method to synthesize β-Ga₂O₃ nanoparticle by utilizing the plant extract for potential application in the photocatalytic dye degradation.