Extremely downsized (including quantum-sized and subnanometer-sized) materials with sizes between atoms and nanoparticles have attracted tremendous attention thanks to their unique structures and exotic physical and chemical properties. Such unusual materials will induce a range of enhanced performances compared with their nanoscale and bulk counterparts, which can be beneficial to driving advancements of materials science as well as nanoscience and nanotechnology. However, it is quite challenging to prepare extremely downsized materials due to their ultrasmall sizes and ultralarge surfaces. Up to now, a variety of strategies have been explored for the preparation of extremely downsized materials, among which the basic categories are top-down and bottom-up methods. The former generally tailors bulk materials into downsized nanomaterials by physical routes, while the latter usually involves chemical (solution) processes to synthesize nanomaterials. During past decades, most efforts have been devoted to bottom-up methods for the synthesis of extremely downsized materials (e.g., colloidal quantum dots, sub-nanometer-sized materials, clusters, and supermolecules). Meanwhile, the production of extremely downsized materials through top-down methods is far from satisfactory, limited by their low manufacturing capacities and relatively expensive facilities. Note that nanomaterials produced by top-down physical methods exhibit entirely exposed surface/edge lattices, while the surface/edge lattices synthesized by bottom-up chemical methods are protected by ligands, making the surface/edge effects greatly obscured. Undoubtedly, exploiting a robust strategy to produce extremely downsized materials with maximized exposed lattices by all-physical top-down methods is required and desired. Our group has been focusing on all-physical production and extreme performances of extremely downsized materials since 2015. We have developed a universal and scalable strategy (i.e., the combination of silica-assisted ball-milling and sonication-assisted solvent exfoliation and treatment) for the all-physical production of quantum-sized materials. A series of quantum-sized materials with intrinsic characteristics have been produced, pushing forward the establishment of a complete database/library. Recently, two-stage silica-assisted ball-milling has been employed to realize the universal production of sub-nanometer-sized materials with entirely exposed and broken intrinsic lattices, suggesting that the top-down fabrication limit has reached the subnanometer (single-lattice) scale. Enhanced performances are demonstrated in both quantum-sized and sub-nanometer-sized materials because of their numerous broken lattices on surfaces/edges.

中文翻译：

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极小的材料尺寸：球磨实现通用生产和尺寸减小带来的性能增强


尺寸介于原子和纳米粒子之间的极小型（包括量子尺寸和亚纳米尺寸）材料由于其独特的结构和奇特的物理化学性质而引起了极大的关注。与纳米级和块状材料相比，这种不寻常的材料将产生一系列增强的性能，这有利于推动材料科学以及纳米科学和纳米技术的进步。然而，由于尺寸超小和表面超大，制备极小的材料非常具有挑战性。到目前为止，已经探索了多种制备极小型材料的策略，其中基本类别是自上而下和自下而上的方法。前者通常通过物理路线将块状材料定制成小型纳米材料，而后者通常涉及化学（溶液）过程来合成纳米材料。在过去的几十年里，大部分精力都致力于自下而上的方法，以合成极小的材料（例如，胶体量子点、亚纳米级材料、团簇和超分子）。与此同时，由于制造能力低且设施相对昂贵，通过自上而下的方法生产极小型的材料远非令人满意。请注意，通过自上而下的物理方法生产的纳米材料表现出完全暴露的表面/边缘晶格，而通过自下而上的化学方法合成的表面/边缘晶格受到配体的保护，使表面/边缘效应大大模糊。 毫无疑问，利用一种稳健的策略，通过全物理自上而下的方法生产具有最大暴露晶格的极小尺寸材料是必要的，也是需要的。自 2015 年以来，我们集团一直专注于全实物生产和极小尺寸的材料的极致性能。我们开发了一种通用且可扩展的策略（即二氧化硅辅助球磨和超声辅助溶剂剥离和处理的组合），用于量子尺寸材料的全物理生产。已经产生了一系列具有内在特性的量子尺寸材料，推动了完整数据库/库的建立。最近，两阶段二氧化硅辅助球磨已用于实现具有完全暴露和破碎本征晶格的亚纳米尺寸材料的普遍生产，这表明自上而下的制造极限已达到亚纳米（单晶格）尺度。量子尺寸和亚纳米尺寸的材料都证明了增强的性能，因为它们的表面/边缘上有许多破碎的晶格。