染料敏化钛酸盐纳米管可见光分解水制氢研究

发布时间：2018-05-04 14:03

  本文选题：钛酸盐纳米管 + 助催化剂　； 参考：《南昌大学》2015年硕士论文

【摘要】：本文主要研究了以水热法合成的钛酸盐纳米管为半导体,进行染料敏化使其在可见光下分解水制氢。研究内容主要分为以下两部分:第一部分:不同镍盐修饰的钛酸盐纳米管通过简单的浸渍—煅烧法制备,以氮氢混合气作为还原剂,研究了不同前驱体对光催化制氢的影响。不同镍盐前驱体通过离子交换,镍离子可以吸附在钛酸盐纳米管的内层和外表面,且大部分镍离子主要吸附在外表面。相对于硝酸镍和醋酸镍作为前驱体,氯化镍作为前躯体进入钛酸盐纳米管夹层的镍离子较多。在400 oC还原煅烧过程中,钛酸盐纳米管转化成二氧化钛,镍离子被还原成纳米颗粒的金属镍,以及部分镍对TiO2和钛酸盐纳米管中进行了掺杂。在以氯化镍作为前驱体的情况下,相的转变以及镍离子的掺杂比以硝酸镍和醋酸镍作为前躯体更有效。内层的Ni2+促进了相的转变、金属镍颗粒的增长和Ni2+掺杂。形成的纳米颗粒的金属镍在空气中被氧化形成Ni@NiO核壳结构。镍离子的掺杂促使了氧空位的形成以及增加了钛酸盐纳米管的导电性。在可见光(λ≥420 nm)照射下,用三乙醇胺(TEOA)作为电子牺牲剂,以曙红敏化镍修饰的钛酸盐纳米管为催化剂进行了光催化制氢研究。与硝酸盐和醋酸盐的镍修饰钛酸盐纳米管相比,用氯化镍修饰的钛酸盐纳米管展现了更高的活性。这可以归因于用氯化镍修饰的钛酸盐纳米管具有更高的导电率和更有效地形成Ni@NiO核壳结构。第二部分:以氯化镍作为前驱体修饰钛酸盐纳米管,进一步研究了还原温度对催化剂制氢活性的影响。在可见光照射下,以三乙醇胺为电子给体,考察了曙红敏化镍修饰的钛酸盐纳米管制氢活性。结果表明,当还原温度为400 oC时,催化剂显示出最好的活性。
[Abstract]:In this paper, the dyestuff sensitization of titanate nanotubes synthesized by hydrothermal method to produce hydrogen from water under visible light was studied. The main contents of the study are as follows: in the first part, the effects of different precursors on photocatalytic hydrogen production were studied by simple impregnation and calcination of titanate nanotubes modified with different nickel salts, using nitrogen-hydrogen mixture as reducing agent. Nickel ions can be adsorbed on the inner and outer surfaces of titanate nanotubes by ion exchange, and most of the nickel ions are mainly adsorbed on the outer surface. Compared with nickel nitrate and nickel acetate as precursors, nickel chloride as precursor enters the interlayer of titanate nanotubes with more nickel ions. During the reduction and calcination of 400oC, titanate nanotubes were converted into titanium dioxide, nickel ions were reduced to metal nickel nanoparticles, and some nickel was doped into TiO2 and titanate nanotubes. In the case of nickel chloride as precursor, the phase transition and doping of nickel ion are more effective than nickel nitrate and nickel acetate as precursors. The Ni2 in the inner layer promotes the phase transition, the growth of nickel particles and the doping of Ni2. The formed nickel nanoparticles were oxidized in air to form Ni@NiO core-shell structure. The doping of nickel ions promotes the formation of oxygen vacancies and increases the conductivity of titanate nanotubes. Under visible light (位 鈮，

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