Investigation into radiolytic preparation of graphene-noble metal nanocomposites with electrocatalytic properties

辐射分解制备具有电催化性能的石墨烯-贵金属纳米复合材料的研究

• 批准号: EP/R042179/1
• 负责人: Aliaksandr Baidak
• 金额: $ 14.74万
• 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: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FR042179%2F1
• 关键词: Investigation; into; radiolytic; preparation; graphene

Metal nanoparticles (NPs) are highly attractive materials for a wide range of applications. Promising fields for NPs commercialisation include fuel cell technology, catalysis, information storage, sensing, photonics and optoelectronics, among many others. However, currently adopted synthetic protocols for production of NPs generally don't allow for the rational control over critical steps of the nucleation and growth of metal nanoparticles. The tendency of NPs to aggregate constitutes another challenge for stable performance of devices based on metal nanoparticles.A sensible strategy to mitigate the aggregation of NPs is to use supporting materials to stabilise metal nanoparticles in a dispersed state. Graphene and its derivative, reduced graphene oxide (rGO), are appealing candidates for such templates. By combining the advantageous properties of graphene with those of metal NPs a powerful synergistic effect in catalytic performance of such nanocomposites is achieved, i.e. the nanocomposite performance appears to be far superior with respect to the individual components. Furthermore, the usage of a carbon support reduces noble metal content of the catalyst while enhancing overall catalytic activity due to the increased active surface area.In order to achieve fully controlled, rational design of metal-decorated nanostructures, advanced synthesis techniques need to be developed. An "ideal" preparation protocol is expected to yield high quality nanomaterials in uniform size, while possessing excellent reproducibility and scalability. Preparation procedure of supported metal nanoparticles shall also avoid the use of harsh chemicals or high temperatures and pressures. The radiation chemical technique proposed in this project meets these essential requirements. The method relies on the use of active reducing species formed in the radiolysis of solvents for prompt and simultaneous reduction of precursor metal ions and GO into zero-valent metal nanoparticles and rGO, respectively. The main advantages of the proposed radiolytic approach are the following: (1) it is a solution-based, one-step, scalable synthesis conducted at ambient conditions; (2) reduction of metal ions can be done in a variety of solvents; wide selection of reducing radicals formed upon radiolysis is available; (3) reducing radicals are produced uniformly in solution, and the rate of their formation can be easily manipulated.In this work, we are going to develop of a new platform for a controlled synthesis of carbon-supported metal nanoparticles, for electrocatalysis applications. More specifically, we will radiolytically synthesise a series of gold and palladium nanoparticles on two different graphene-based supports and in four different solvents. This work will endeavor to close the gap in understanding of the effect of complexation between precursor metal ions and graphene-based templates on the relevant properties of synthesised nanocomposites. We will also explore whether the radiation chemistry of a solvent, deployed for the reduction reaction, can be used to effectively manipulate the shape and size-dependent properties of the metal-decorated nanomaterials. The catalytic efficiency of the synthesised nanocomposites will be screened by performing the electrooxidation of glucose into gluconic acid in alkaline conditions. Subsequently, prepared nanocatalysts will be fully characterised in terms of their size, structure and composition. Such elaborate analysis will allow us to gain a better understanding of observed "structure-property" relationships, thus creating the scientific basis for a controlled design of nanomaterials using radiation chemical approach.

金属纳米颗粒(NPs)是一种具有广泛应用前景的极具吸引力的材料。NPs商业化的前景广阔的领域包括燃料电池技术、催化、信息存储、传感、光电子学和光电子学等。然而，目前所采用的合成纳米粒子的方法一般不允许对金属纳米粒子的成核和生长的关键步骤进行合理的控制。纳米粒子的聚集趋势对基于金属纳米粒子的器件的稳定性能构成了另一个挑战。缓解纳米粒子聚集的一个明智的策略是使用支撑材料来稳定分散状态的金属纳米粒子。石墨烯及其衍生物还原石墨烯氧化物(RGO)是此类模板的热门候选材料。通过结合石墨烯和金属纳米粒子的优点，这种纳米复合材料在催化性能上实现了强大的协同效应，即纳米复合材料的性能表现出远远优于单个组分的性能。此外，碳载体的使用减少了催化剂中的贵金属含量，同时由于活性表面积的增加而提高了整体催化活性。为了实现完全可控的、合理的金属修饰纳米结构的设计，需要开发先进的合成技术。理想的制备方案应能制备出尺寸均匀的高质量纳米材料，同时具有良好的重复性和可扩展性。负载型金属纳米颗粒的制备程序还应避免使用苛刻的化学品或高温高压。本项目提出的辐射化学技术满足了这些基本要求。该方法依赖于利用溶剂辐解过程中形成的活性还原物种来迅速和同时还原前驱体金属离子，并分别转化为零价金属纳米颗粒和rGO。提出的辐射分解方法的主要优点是：(1)它是一种基于溶液的一步可扩展的常温合成方法；(2)金属离子可以在各种溶剂中进行还原；(3)还原自由基在溶液中生成均匀，其形成速度易于控制。在这项工作中，我们将开发一种新的平台，用于控制合成碳负载金属纳米颗粒，用于电催化应用。更具体地说，我们将在两种不同的石墨烯载体上和四种不同的溶剂中辐射合成一系列金和钯纳米颗粒。这项工作将努力弥合前驱体金属离子和石墨烯模板之间的络合作用对合成的纳米复合材料相关性能的影响这一认识上的差距。我们还将探索用于还原反应的溶剂的辐射化学是否可以有效地操纵金属装饰纳米材料的形状和尺寸依赖的性能。通过在碱性条件下将葡萄糖电氧化为葡萄糖酸来筛选所合成的纳米复合材料的催化效率。随后，制备的纳米催化剂将根据其大小、结构和组成进行充分表征。这种精细的分析将使我们能够更好地了解观察到的“结构-性质”关系，从而为使用辐射化学方法进行纳米材料的受控设计创造科学基础。

项目成果

Two Birds with One Stone: Concurrent Ligand Removal and Carbon Encapsulation Decipher Thickness-Dependent Catalytic Activity.

• DOI: 10.1021/acs.nanolett.2c03181
• 发表时间: 2022-11-09
• 期刊: NANO LETTERS
• 影响因子: 10.8
• 作者: Guo, Kun;Chang, Litao;Li, Ning;Bao, Lipiao;Shubeita, Samir de Moraes;Baidak, Aliaksandr;Yu, Zhixin;Lu, Xing
• 通讯作者: Lu, Xing

Recent advances in green synthesis and modification of inorganic nanomaterials by ionizing and non-ionizing radiation

• DOI: 10.1039/d0ta06742c
• 发表时间: 2020-11
• 期刊: Journal of Materials Chemistry
• 作者: K. Guo;A. Baidak;Zhixin Yu