论文总字数：19962字

摘 要

当今社会，伴随着不可再生能源的大量消耗以及生态环境的日益脆弱，如何高效的存储及利用可再生清洁能源成为大家关注的焦点。太阳能作为一种重要的可再生能源，如果能获得高效且持久利用太阳能的科学方法，将会对人类社会的可持续发展起到重要的作用。

在致力于实现光能和化学能、热能等能量的转化中，利用半导体催化剂进行光催化分解水制得氢气及还原CO2制得有机物技术获得了较快的发展。由于其制作成本较低加上高效的能源利用，寻找一种合适的半导体催化剂材料得到了世界的广泛关注和研究。

在各种光催化材料中，由于SrTiO3半导体具有较好的电子空穴分离运输特性，与较为匹配的能带位置，而成为一种良好的光催化材料。

本文把常用的半导体催化材料SrTiO3作为研究对象，结合光催化分解水的基本机理，讨论半导体材料结构的带隙，结晶性和比表面积的大小对于材料催化性能的影响。

本文主要研究内容和结论如下：

多孔纳米SrTiO3半导体材料形成机制研究。

本实验采用的方法是碱性熔盐法制备多孔纳米SrTiO3半导体，理论研究发现

熔融氢氧化物由于其粘度大、高密度而在反应物多孔结构的形成中发挥关键作用。在本实验中我们把NaOH/KOH溶液混合作为熔盐，高粘度的熔融氢氧化物在较低反应温度下离子的扩散速度较慢，从而使得所合成SrTiO3材料呈多孔纳米晶状。

通过本实验合成的多孔纳米SrTiO3材料可以具有较大的比表面积系数和良好的结晶性。在这个过程中，我们将对前驱物种类，样品合成及处理方法，清洗温度变化，反应时间长短等进行实验变量控制.分析不同情况下SrTiO3结构的变化，从而在获得较高的光催化制氢活性SrTiO3样品时，总结多孔纳米SrTiO3半导体的形成机制。以上就是本实验研究的主要内容。

关键词：SrTiO3， 光催化析氢， 多孔纳米结构， 碱性熔盐法， 再结晶

Formation mechanism of porous nano SrTiO3 semiconductor

Abstract

Nowadays, with a large number of nonrenewable energy consumption and increasingly fragile ecological environment, how to store and use renewable clean energy effectively has become the focus of attention in our society. As an important renewable energy, it will play an important role in the sustainable development of human society if we can acquire the scientific method of efficient and long-term use of solar energy.

In the conversion of light energy and chemical energy, the technology of using semiconductor catalyst for photocatalytic decomposition of water to produce hydrogen and reduce the CO2to produce organic compounds has been developed rapidly.

Due to its low production cost and high efficient energy use, it has been widely concerned and studied in the world to find a suitable semiconductor catalyst material.

In a variety of photocatalytic decomposition of water materials, the SrTiO3semiconductor has become a good photocatalytic material because of its better separation and transport characteristics of electron and hole.

Based on the basic mechanism of photocatalytic decomposition of water, SrTiO3semiconductor catalytic material is used as the object of study in this paper.

The effect of band gap, crystallinity and specific surface area of semiconductor materials on the performance of hydrogen production from decomposition of catalytic materials was studied through theoretical analysis and experimental verification,

The main contents and conclusions of this paper are as follows:

According to the basic principle of photocatalytic decomposition, the microstructure of the photocatalytic material has an important influence on its catalytic performance.From the chemical point of view, in order to increase the binding site of the reaction and improve the activity of the reaction, idealphotocatalyst should have a large specific surface area, good crystallinity and high light absorption efficiency.

The method used in this study is basic molten salt route to prepare porous SrTiO3Nanocrystals. Molten hydroxide is believed to play a key role in the formation of cell surface due to its high viscosity and high density.

In this experiment, we mixed the NaOH/KOH solution as molten salt. The diffusion rate of ions at lower reaction temperature is slower in high viscosity molten hydroxide, which makes the SrTiO3 material in the form of porous nanocrystalline . The porous nano SrTiO3 materials prepared by this experiment can have large specific surface area coefficient and good crystallinity, and thus having high photocatalytic hydrogen evolution rate.

In this process, the changes of precursor species, sample synthesis and processing methods, cleaning temperature changes, reaction time will be in control.The changes of SrTiO3 structure under different conditions are analyzed to summarize the formation mechanism of porous nano SrTiO3 semiconductor when the higher photocatalytic activity of SrTiO3 samples was obtained. the main content of the experimental study is above.

Key words: SrTiO3, photocatalytic hydrogen evolution, porous nano structure, basic molten salt method, recrystallization.

目录

摘要…………………………………………………………. II

Abstract………………………………………………………… ..IV

第一章 绪论……………………………………… …………………………………1

1.1光催化分解水的研究背景 …….………….…………………………...……1

1.2 光催化分解水制氢的基本原理……….……………………………………..1

1.3 催化材料分解水产氢性能的影响因素………………………. ……...……...2

1.3.1 带隙……………………………………………………………..……2

1.3.2 结晶性………………………………………………………..………2

1.3.3 比表面积.……………………………………………………….……3

1.4 光催化材料的研究进展……………………………………………….…….3

1.4.1传统宽带隙半导体材料的改进……………………………….……3

1.4.1.1带隙的改变…………………………………………...………...4

1.4.1.2电子空穴对的分离………………………………………… …5

1.4.1.3参与反应的电子或空穴的增加………………………………5

1.4.1.4双光子体系同时产氢产氧……………………………………5

1.4.2 新型窄带隙半导体材料的研发………………………………...…..5

1.5 SrTiO3半导体的研究历史………………………………………………6

1.6本文研究内容与意义………….…………………………………..……...6

参考文献…………………………………………………………………………..…7

第二章 实验…………………………………………………………………..……10

请支付后下载全文，论文总字数：19962字