摘要
首先采用水热法在FTO衬底上制备出α-GaOOH纳米柱阵列,再以α-GaOOH纳米柱/FTO结构作为前驱体进行水热反应,经溶解再结晶过程,α-GaOOH纳米柱可转变为边长约为500 nm的ZnGa_2O_4纳米立方块。在模拟太阳光源辐照下的一系列光催化实验结果表明:样品对亚甲基蓝具有较强的吸附作用和较高的光催化活性,对罗丹明B、刚果红的吸附能力和光催化作用都很弱,对甲基橙只有较弱的光催化作用;H_2O_2可以作为电子捕捉剂和供氧剂,促进样品的导带电子参与活性自由基的形成,使样品对染料表现出持续较高的光催化活性。
α-GaOOH nanorod arrays on FTO substrates are synthesized by a simple hydrothermal method for the first time, which can be used as a precursor and converted via hydrothermal reaction into ZnGa_2O_4 nanocubes due to a dissolution-recrystallization process. The characterization results of samples indicate that as-prepared ZnGa_2O_4 on FTO belongs to cubic system and has the cubic morpohology with the size of about 500 nm. A series of photocatalytic experiments have been performed under simulated sunlight irradiation and the results indicate that ZnGa_2O_4 nanocubes show both enhanced adsorption and photocatalytic abilities for methylene blue compared with rhodamine B and congo red, and only show weak photocatalytic activity for methyl orange. As electron scavenger and oxygen provider, H_2O_2 can facilitate the formation of free radicals with high chemical reactivity and make as-prepared samples possess continuous and enhanced photocatalytic activity of dyes.
引文
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