Substituent and anchor group effects in bonding to TiO2 Single Crystal Surfaces: Enhancing Solar Conversion Efficiency and Corrosion Inhibition.

取代基和锚定基团对 TiO2 单晶表面键合的影响：提高太阳能转换效率和腐蚀抑制。

基本信息

批准号：
EP/M026817/1
负责人：
Andrew THOMAS
金额：
$ 0.63万
依托单位：
University of Manchester
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2015
资助国家：
英国
起止时间：
2015 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FM026817%2F1
关键词：
Substituent anchor group effects bonding

项目摘要

With concerns over the environmental impact of fossil fuel use and the issue of sustainability of fossil fuels, generation of fuels such as hydrogen or methanol and direct generation of electricity from nanoengineered materials is an area of considerable interest. Titanium dioxide (TiO2), for example, has long been known to be capable of producing hydrogen from water under illumination and can also be used to generate a photo voltage. However TiO2 absorbs in the ultraviolet region of the electromagnetic spectrum, and the amount of ultraviolet at the earth's surface is relatively low, when compared to visible light. One approach to enhance absorption of visible light is to functionalise the oxide with a material which will absorb in the visible region of the solar spectrum followed by charge transfer to the TiO2 which then drives the photoelectrochemical reaction or produces the photovoltage. This has led to the advent of dye sensitised solar cells, or the so called Graetzel cell which have an efficiency of around 15 %. These dyes are often bound to the nano structured TiO2 by carboxylic acid (COOH) groups to form Ti-O-C-O-Ti + H at the surface. The ordering, and therefore the packing density, and strength of bonding thought to play a part in the efficiency of the cells, since ultimately they control the charge transfer from the dye to the surface. Defects in the TiO2 substrate are also thought to contribute to limitations in efficiency.Changing the chemistry of substituent groups on benzoic acids affects the acidity of the carboxyl group, and make it more or less likely to give up its proton when it attaches to the oxide material. We wish to study whether this change in the acidity has an effect on the boding strength of the molecules. We also wish to investigate whether having three oxygen atoms, as found in phosphonic acid (R-P=O(OH)2) where R is an organic side chain or ring (here we will study R=C6H5). Synchrotron radiation allows us to utilise tunable X-rays to determine the geometry of the molecules when they are adsorbed on the surface. It also allows us to look at where the electrons are in the material and recently we discovered that we can "see" electrons being injected into the TiO2 substrate when a dye-molecule is attached to the surface, via a spectroscopic fingerprint. We wish to use this fingerprint to determine how efficiently charge is injected into the surface. In addition the techniques available at the synchrotron allow us to determine the chemistry of the molecule, and importantly its stability. Clearly any dye molecule must remain stable in order for a device to work, and loss of the bonding to the substrate would have a negative impact. This fundamental work should allow chemists designing dyes to choose the most appropriate side groups to ensure strong bonding to the TiO2 and to obtain the maximum efficiency for a particular dye.

人们担心化石燃料的环境影响以及化石燃料的可持续性问题，氢或甲醇等燃料的产生以及纳米工程材料的直接发电是一个引起了人们极大兴趣的领域。例如，二氧化钛（TIO2）长期以来一直在照明下能够从水中产生氢，也可以用于产生光电电压。但是，与可见光相比，Tio2在电磁谱的紫外线区域吸收，地球表面的紫外线量相对较低。增强可见光吸收的一种方法是，用一种将吸收在太阳光谱的可见区域中吸收氧化物，然后电荷转移到TiO2中，然后将光电化学反应驱动或产生光电压。这导致染料敏化的太阳能电池或所谓的Graetzel电池的出现，其效率约为15％。这些染料通常与羧酸（COOH）基团结合到纳米结构的TiO2，以在表面形成TI-O-C-O-TI + H。订购，因此堆积密度和粘结强度被认为在细胞的效率中起着作用，因为它们最终控制了从染料到表面的电荷转移。 TIO2底物中的缺陷也被认为有助于效率的局限性。苯甲酸上的化学基团的化学因素会影响羧基的酸度，并在其附着在氧化物材料上时，它或多或少地放弃其质子。我们希望研究酸度的这种变化是否对分子的鸟类强度有影响。我们还希望研究是否具有三个氧原子，如磷酸（R-P = O（OH）2）中发现，其中R是有机侧链或环（在这里我们将研究r = C6H5）。同步加速器辐射使我们能够利用可调的X射线来确定分子在表面吸附时的几何形状。它还使我们能够查看材料中的电子的位置，最近我们发现，当染料 - 分子连接到表面，通过光谱指纹将电子“看到”被注入TiO2底物。我们希望使用此指纹来确定如何有效地将电荷注入表面。另外，在同步加速器上可用的技术使我们能够确定分子的化学性质，并且重要的是它的稳定性。显然，任何染料分子都必须保持稳定，以使设备起作用，而与底物的键失去将产生负面影响。这项基本工作应允许化学家设计染料，以选择最合适的侧面组，以确保与TIO2的牢固粘合并获得特定染料的最大效率。

项目成果

期刊论文数量（4）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Ionic Liquid Ordering at an Oxide Surface.

DOI：
10.1002/cphc.201600774
发表时间：
2016-11-04
期刊：
Chemphyschem : a European journal of chemical physics and physical chemistry
影响因子：
0
作者：
Wagstaffe M;Jackman MJ;Syres KL;Generalov A;Thomas AG
通讯作者：
Thomas AG

A one-step laser process for rapid manufacture of mesoscopic perovskite solar cells prepared under high relative humidity