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Effects of surfactants on the morphology and properties of ­TiO2 Hong‑Xia Wang1,2   · Xin‑Xing Li1,2 · Liang Tang1 Received: 20 November 2019 / Accepted: 15 May 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020

Abstract TiO2 nanoparticles with controllable morphology perform well in both physical and chemical properties, which have great significance in photocatalytic degradation of wastewater and photodegradation of water. In this study, ­TiO2 was prepared by solvothermal method with tetrabutyl titanate as titanium source, acetic acid as solvent and surfactant as additive. The effects of single and mixed surfactants, such as cetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG) and carboxamide, on the microstructure of ­TiO2 were systematically studied. The results showed that the prepared ­TiO2 was anatase phase. It clearly demonstrated the procedure how the morphology and size of ­TiO2 were influenced by surfactant. In the reaction system, when carboxamide was added to T ­ iO2, CTAB or PEG, T ­ iO2 nanocrystals gathered to form rod, cluster or similar ellipse, respectively. When two or more different surfactants were added to the system simultaneously, the morphology of T ­ iO2 could be cauliflower-like, spherical and three-dimensional flower-like structures formed by the directional aggregation of nanocrystals due to the coordination between the surfactants. The photocatalytic properties of methyl orange were investigated under UV irradiation. The results showed that the photocatalytic properties of cauliflower-like structures, spherical structures and three-dimensional flower-like structures formed by the directional aggregation of nanocrystals were better than those of commercial Degussa P25. T ­ iO2 nanoparticles with three-dimensional flower-like structures exhibited good photocatalytic performance, with the degradation ratio of methyl orange 94% under simulated irradiation for 60 min. Keywords  Surfactant · Photocatalysis · Solvothermal method · Specific surface area

1 Introduction Semiconductor photocatalysis is considered to be an effective solution which has been widely used in treatment of water pollution in recent years [1–3]. ­TiO2 has been considered as an ideal photocatalytic material because of its wideband gap, low cost, non-toxic and excellent chemical stability [4–7]. ­TiO2 can degrade organic matter in sewage into ­CO2 and ­H2O, avoiding the problem of secondary pollution. The research shows that the different morphologies and structures of photocatalysts directly affect their optical and photocatalytic properties [8–11]; therefore, controllable preparation of ­TiO2 morphology is an effective way to improve photocatalytic activity [12–15]. The morphology * Hong‑Xia Wang [email protected] 1



Department of Information and Engineering, Suqian College, 399 South Huanghe Road, Suqian 223800, China



Suqian Key Laboratory for Functional Materials, Suqian College, 399 South Huanghe Road, Suqian 223800, China

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of ­TiO2 can be controlled by the synthesis route and