In recent years, the field of catalysis has experienced an astonishing transformation, driven in part by more demanding environmental standards and critical societal and industrial needs such as the search for alternative energy sources. Thanks to the advent of nanotechnology, major steps have been made towards the rational design of novel catalysts. Striking new catalytic properties, including greatly enhanced reactivities and selectivities, have been reported for nanoparticle (NP) catalysts as compared to their bulk counterparts. However, in order to harness the power of these nanocatalysts, a detailed understanding of the origin of their enhanced performance is needed. The present review focuses on the role of the NP size and shape on chemisorption and catalytic performance. Since homogeneity in NP size and shape is a prerequisite for the understanding of structure–reactivity correlations, we first review different synthesis methods that result in narrow NP size distributions and shape controlled NPs. Next, size-dependent phenomena which influence the chemical reactivity of NPs, including quantum size-effects and the presence of under-coordinated surface atoms are examined. The effect of the NP shape on catalytic performance is discussed and explained based on the existence of different atomic structures on the NP surface with distinct chemisorption properties. The influence of additional factors, such as the oxidation state of the NPs and NP–support interactions, is also considered in the frame of the size- and shape-dependency that these phenomena present. Ultimately, our review highlights the importance of achieving a systematic understanding of the factors that control the activity and selectivity of a catalyst in order to avoid trial and error methods in the rational design of the new generation of nanocatalysts with properties tunable at the atomic level.

近年来，催化领域经历了惊人的转变，部分原因是更严格的环境标准和关键的社会和工业需求，例如寻找替代能源。由于纳米技术的出现，朝着合理设计新型催化剂迈出了重要的一步。纳米颗粒（NP）催化剂与其本体催化剂相比，具有惊人的新催化性能，包括大大提高的反应性和选择性。然而，为了利用这些纳米催化剂的力量，需要对其增强性能的起源有详细的了解。目前的审查集中在NP大小和形状对化学吸附和催化性能的作用。由于NP大小和形状的均一性是理解结构与反应性相关性的先决条件，因此我们首先回顾一下导致NP大小分布狭窄和形状受控的NP的不同合成方法。接下来，研究了影响NPs化学反应性的尺寸依赖性现象，包括量子尺寸效应和配位不足的表面原子的存在。讨论并解释了NP形状对催化性能的影响，基于NP表面具有不同的化学吸附特性的不同原子结构的存在。在这些现象存在的大小和形状相关性的框架内，还考虑了其​​他因素的影响，例如NP的氧化态和NP与支持物的相互作用。最终，