功能化联噻唑钌、钴和铜配合物的合成与光催化水制氢研究

The global energy resources are mainly from fossil fuels (oil, coal and gas), in which the fossil fuel supplies are assumed to be depleted in several years. The combustion of these fossil fuels has caused a series of critical environmental problems, ranging from air and water contamination to global warming. Hence, seeking an alternative clean energy is urgently needed. Among all of the renewable sources, solar energy is one of the most feasible and attractive energy sources. And thus, there is an ever-growing need for the harvest and conversion of solar energy into a usable energy.Recent advances in photocatalytic H2 generation under visible light irradiation has been shown a myriad of inorganic semiconductors photocatalysts, including oxides, sulfides and oxynitrides. However, there exists some intrinsic drawbacks among them, such as poor optical absorption ability for wide band gap oxides, poor photochemical stability for sulfides, and complicated preparation processes for oxynitrides, still significantly limit their practical application for photocatalytic solar-hydrogen conversion. Compared with those inorganic semiconductor-based photocatalysts, organometallic complexes have demonstrated efficient visible light absorption and good photochemical stability, as well as facile preparation methods.A series of novel photocatalysts were synthesized successfully and characterized. Through the optimization of the proportion of each component, the best photocatalytic performance was observed for composite 6 (2.0 wt% C60). It also exhibits an exceptionally high rate of hydrogen production at 7.39 mmol h1 g1 under visible light illumination, and shows relatively high reusability. More importantly, this work not only offers a stable and efficient nanocomposite photocatalyst but also sheds light on new inroads for engineering cost-effective nanocomposites, which could open up new insights to promote the improvement of photocatalytic conversion efficiency for metal complexes.

各国能源消耗持续增长,石油、煤、天然气传统燃料储量有限,能源需求面临严峻挑战.因此,开发清洁能源代替化石能源,成为全人类共同目标.氢能源作为一种清洁能源,是当前国内外研究热点之一,对解决能源紧缺、减小环境污染等问题具有重要意义.光催化水制氢引起国内外专家兴趣.常用光催化剂主要有两种,1)无机半导体材料,2)有机金属配合物半导体材料。虽然无机半导体材料价格比较便宜,由于它们仅能吸收紫外光,大部分可见光不能利用;有机金属配合物因其独特的光催化活性,特别是在可见光区域,越来越受到人们的关注.随着光催化水制氢研究的不断深入,过渡金属类配合物如钌、钴、铜都具有未填满的轨道,作为光生电子和空穴分离中心,利于光催化剂吸收可见光,合成能高效吸收可见光的过渡金属配合物,利于提高光量子产率.是本申请项目设计合成有机功能化联噻唑金属配合物的目的.初步与C60共催化效果显著,将进一步扩展与纳米金属共催化研究.

本项目光催化制氢作为一种具有前景的能源转化方式，受到了广泛关注。但是光催化过程中的三个步骤(光吸收、载流子分离、表面反应)效率较低，目前难以实现工业应用。合成了系列功能化Co-2TPABTz光催化剂和系统表征了其结构，证实了优异的光催化水制氢活性，含10%Ag纳米颗粒的光催化剂产氢达到20.65 mmol h−1g−1。增强光催化活性是由于多孔的Co-2TPABTz与表面等离子体Ag NPs的协同作用。虽然无机半导体材料价格比较便宜,由于它们仅能吸收紫外光,大部分可见光不能利用;有机金属配合物因其独特的光催化活性,特别是在可见光区域,越来越受到人们的关注.随着光催化水制氢研究的不断深入,过渡金属类配合物如钌、钴、铜都具有未填满的轨道,作为光生电子和空穴分离中心,利于光催化剂吸收可见光,合成能高效吸收可见光的过渡金属配合物,利于提高光量子产率.这类新型的光催化剂不仅前景光明，而且具有潜在的应用。本研究聚焦于宽光谱吸收、用Ag和Cu纳米粒子作为表面等离子体，有效的分离光生电子-空穴对、表面反应的机理和改性光催化剂的制氢应用，构建高效制氢光催化剂。