贵金属基纳米复合材料将贵金属和其他类别的组分结合在一起，使得复合材料具有独特的物理化学特性，在光催化、药物合成、环境催化、电催化和氧化/燃烧反应等领域表现出良好的应用前景。现在贵金属基纳米复合材料的合成方法主要是水相合成和有机相合成，水相合成需要用到非常贵重的化学试剂，且前驱体浓度不能太高，难以推广和大规模制备。有机相合成需要避免金属壳层在内核表面的过度沉积，则金属内核必须占据较大比例，但这样活性金属暴露出的面积较小，参与催化反应的活性面积较小，不利于催化反应的进行。因此，提高单位贵金属的催化性能，降低贵金属的用量成为当前的研究重点。本论文从材料学的观点着手，对催化剂的结构进行调控，利用调控过程中改变的电子结构和调控出的纳米材料的结构优势，以期提升贵金属基纳米复合催化剂的电化学催化和环境催化活性。基于这个整体思路，设计从提高原子分散度和利用空心结构的角度出发，来提高贵金属原子的利用率。首先是从提高原子分散度的角度，实现贵金属的原子分散，并测定其苯催化氧化性能。具体来说，先将铜（Cu）离子在油胺中还原得到Cu颗粒，再将钯（Pd）离子的前驱体与之进行伽伐尼置换（GRR）得到Cu-Pd双金属合金，将其负载在γ-氧化铝（γ-Al2O3）上，控制温度，将Cu氧化而Pd保持0价态，相当于Pd呈原子级别分散于氧化铜（CuO）上。将制备得到的贵金属-氧化物纳米复合催化剂进行苯氧化性能测试，结果表明，当Pd含量增加时，催化性能更好。除了Pd含量的影响，苯催化氧化的活性也与Pd的分散性有关。当Pd含量降低，其分散度会增加，可以有效防止Pd原子的团聚，从而提高每个活性位点的催化活性。同时，催化剂也表现出了良好的稳定性和抗水汽性能。该方法结合伽伐尼置换和氧化处理，节约了贵金属的用量，且贵金属能和氧化物充分接触，不易团聚，从而高效利用贵金属组分，提升催化性能。此外，本文利用空心结构的优势提高贵金属的利用率，并考察了贵金属-半导体纳米复合材料的生长机制。首先在油胺中制备得到银（Ag）纳米颗粒，以此为种子还原铂（Pt）离子得到的核壳Ag@Pt纳米颗粒再与不同的硫（S）源反应，通过观察不同结构转换过程中形成的产物的透射电子显微镜（TEM）图像，提出了以核壳Ag@Pt纳米颗粒为起始材料生成硫化银-空心铂复合纳米材料（Ag2S-hPtNCs）的机理，并设计了额外的实验证实了提出的纳米复合材料形成机制的合理性。将该催化剂应用于甲醇电催化氧化反应（MOR）中，由于复合纳米催化剂中各组分之间的强电子耦合作用，在酸性条件下，负载在活性炭（C）上的Ag2S-hPtNCs/C催化剂表现出优异的电催化甲醇氧化反应活性。复合材料中产生电子耦合效应是由于贵金属与半导体之间的电荷传递。电子结构的改变能够有效调节贵金属的d 轨道态密度中心和表层原子的电子云密度，这将更好地平衡电化学反应中反应物及中间产物在贵金属原子表面的吸附，减少一氧化碳（CO）中毒，从而使其表现出最优的催化性能。;Due to the combination of noble metals and other components, noble metal-based nanocomposites show unique physical and chemical properties in areas such as photocatalysis, pharmaceutical synthesis, environmental catalysis, electrocatalysis and oxidation/combustion reactions.The noble metal-based composite nanomaterials are now mainly obtained by aqueous phase synthesis and organic phase synthesis. Aqueous phase synthesis requires the use of very expensive chemical reagents and low concentrations of precursors, making it difficult to prepare on a large scale. The metal core obtained by organic phase synthesis must occupy a large proportion to avoid excessive deposition of the metal shell on the surface of the core, but the exposed area of the active metal and the active area participating in the catalytic reaction are small, which is not conducive to the catalytic reaction. Therefore, the current research focus is to reduce the amount of noble metals and improve the catalytic performance of unit noble metals. In this paper, the structure of noble metal-based nanocomposites are regulated in order to enhance their electrochemical catalysis and environmental catalytic activity by utilizing the altered electronic structure in the regulation process and the structural advantages of the modified nanomaterials. Based on this overall idea, the paper specifically improves the utilization of noble metal atoms through increasing the atomic dispersion and utilizing the advantages of hollow structures.Firstly, the atom dispersion of noble metals is realized from the point of view of improving the atom dispersion. Specifically, this strategy involves the synthesis of copper (Cu) nanoseeds in oleylamine, the galvanic replacement reaction (GRR) between Cu seeds and palladium (Pd) ions for forming bimetallic Cu-Pd nanoalloys, the deposition of Cu-Pd nanoalloys on γ-aluminum oxide (γ-Al2O3) substrates, and the subsequent thermal treatment for oxidizing the Cu component in the alloy particles. It corresponds to the fact that Pd alloys are dispersed in copper oxide (CuO) at an atomic level. Then the prepared noble metal-oxide nanocomposites were tested for the catalytic oxidation of benzene. The results showed that the catalytic performance is better when the Pd content is increased. In addition to the influence of Pd content, the activity of benzene catalytic oxidation is also related to the dispersibility of Pd. When the Pd content is decreased, the degree of dispersion is increased, and the agglomeration of Pd atoms can be effectively prevented, thereby increasing the catalytic activity of each active site. At the same time, the catalysts also showed good stability and water vapor resistance performance. The method combines GRR with thermal treatment and saves the amount of noble metals, which make it possible to efficiently utilize noble metal components and improve the catalytic performance.In addition, we utilizes the advantages of hollow structure and investigates the growth mechanism of noble metal-semiconductor composite nanomaterials. The core-shell Ag@Pt nanoparticles were firstly obtained from silver (Ag) nanoseeds and platinum (Pt) ion, and then reacted with different sulfur (S) sources. By observing the TEM images of the products formed during the different structural transformation processes, the formation mechanism of silver sulfide-hollow platinum nanocomposites (Ag2S-hPtNCs) was proposed. Then the catalyst was applied to the methanol oxidation reaction (MOR). Due to the strong electron coupling between Ag2S and hPt in the Ag2S-hPtNCs/C nanocomposites, Ag2S-hPtNCs/C showed excellent MOR performance under acidic conditions. The electron coupling effect in the composite is due to the charge transfer between the noble metal and the semiconductor. The change of the electronic structure can effectively adjust the density of the d-orbital density center of the noble metal and the electron cloud density of the surface atom, which could better balance the adsorption of reactants and intermediates on the surface of the noble metal atoms during MOR and reduce CO poisoning, thereby exhibiting the best catalytic performance.