BiOI基半导体薄膜材料的制备及其光催化防污性能研究

发布时间：2018-03-14 16:41

  本文选题：生物污损　切入点：BiOI　出处：《中国科学院大学(中国科学院海洋研究所)》2017年硕士论文　论文类型：学位论文

【摘要】：海洋生物污损影响海洋工程材料的正常服役,是人类开发利用海洋难以回避的问题。因此,研发新型、高效、环保防污材料具有重要的现实意义。光催化防污技术以其低能耗、环境友好等优点受到越来越多的关注。为克服传统光催化材料(如TiO_2)对太阳能利用效率低以及光催化粉体材料回收难等缺点,本论文以BiOI可见光催化半导体材料为研究对象,发展了在常温常压下具有纳米分级结构四方相BiOI单体材料的简易制备方法。在此基础上采用原位生长技术实现了BiOI在金属基体上的薄膜化,并进一步采用离子交换法将BiOI单体薄膜加以改性制得BiOI/BiOBr二元半导体复合薄膜材料。具体研内容如下:(1)通过控制共沉淀反应条件,在常温常压不添加表面活性剂的条件下实现了具有花球状分级结构BiOI单体纳米材料的可控合成。在可见光激发下,实现了对污损细菌的高效杀灭。杀菌机理研究表明:h+和·O_2-自由基的产生致使细菌细胞壁膜的破坏是BiOI在水体环境中保持高效光催化杀菌性能的根本原因。(2)利用无机晶体原位生长技术,首次实现了在金属基体(304SS)表面构建具有良好光催化活性的BiOI薄膜。优化各制备工艺参数后,在140 ℃,PVP为0.10 g,反应时间为4 h条件下,制备了物理结构及光化学性质稳定性最佳的BiOI薄膜材料。薄膜呈纳米分级结构,均匀覆盖于金属基体表面,其光催化活性与BiOI粉体材料相比无明显下降。对海洋污损模式细菌及污损藻类显示出良好的光催化杀灭及防附着性能。(3)以四丁基溴化铵(TBAB)为溴源,采用离子交换方法,在304SS基体表面成功构筑了具有p-n异质结结构的BiOI/BiOBr二元复合半导体薄膜材料,与BiOI单体薄膜材料相比其光催化活性明显提高。此外,研究证实了其对细菌胞质内遗传物质(环状质粒DNA)具有光催化开环破坏作用,进一步丰富了光催化材料的杀菌防污机理。
[Abstract]:Marine fouling affects the normal service of marine engineering materials, which is an unavoidable problem for human exploitation and utilization of the ocean. Therefore, it is of great practical significance to develop new, efficient and environmentally friendly antifouling materials. Photocatalytic antifouling technology has its low energy consumption. Environmental friendliness has attracted more and more attention. In order to overcome the disadvantages of traditional photocatalytic materials (such as TiO-2), such as low efficiency of solar energy utilization and difficulty in recovering photocatalytic powder materials, this paper focuses on BiOI visible light catalyzed semiconductor materials. A simple preparation method of tetragonal BiOI monomers with nanometer graded structure at room temperature and atmospheric pressure was developed. On the basis of this, the thin films of BiOI on metal substrates were realized by in situ growth technique. Furthermore, the BiOI monomers were modified by ion exchange method to prepare BiOI/BiOBr binary semiconductor composite films. The specific contents are as follows: 1) by controlling the coprecipitation reaction conditions, The controllable synthesis of BiOI monomeric nanomaterials with flower-like graded structure has been realized under the condition of normal temperature and atmospheric pressure without the addition of surfactants. The bactericidal mechanism shows that the destruction of cell wall membrane caused by the generation of% h and 路O 2- free radicals is the fundamental reason why BiOI maintains high efficiency photocatalytic bactericidal activity in water environment. In situ growth technology of mechanical crystals, The BiOI thin films with good photocatalytic activity on the surface of metal substrate 304SS were fabricated for the first time. After optimizing the preparation process parameters, under the conditions of 0.10 g at 140 鈩，

本文编号：1612057