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Carbon nanotubes are porous materials with a graphite structure that are curled up in a regular pattern to form nanoscale tubular structures; they are important members of the family of carbon materials that have been extensively studied since the 1990s. Depending on the preparation conditions, the inner diameter of carbon tubes can be adjusted from sub-nanometers to several dozen nanometers. When the graphite structure that makes up the carbon tube wall curls with a certain curvature, the conventional large π bonds become distorted, the electron distribution inside and outside the tube changes, which leads to a separation of charges near the tube wall; as a result, an apparent electrostatic field directed from inside the tube to outside is formed. This small potential difference existing inside and outside the carbon tube (estimated to be around 0.05–0.2 electron volts) gives rise to a series of unique physical and chemical properties in nanocarbon tubes that differ from those of other carbon materials. As a catalytic process in important chemical reactions, its key step involves electron transfer between the reactant molecules and the catalyst surface. In principle, this potential difference between the inside and outside of the nanocarbon tubes will alter the electron transfer properties within and outside the tubes, which will inevitably have an impact on catalytic reactions as well. In recent years, several international research groups (including the research group led by Zhang Hongbin from Xiamen University) have utilized the metallic properties of nanocarbon tubes as additives, thereby enhancing the reactivity and selectivity in several catalytic reaction systems and achieving satisfactory results. The research work of Bao Xin and his team focuses on the assembly of catalytically active components within nanotube channels, with an emphasis on studying the effect of the confinement effects in these nanosystems on catalytic reactions. This research achievement involves two important technical advancements: one is the development of methods for cleaning and chemically tailoring freshly prepared carbon tubes. Metal particles (such as silver and iron) are controlled to be deposited on the outer surface of carbon tubes; through their catalytic oxidation, defects are introduced into the surface of these carbon tubes. Further acid etching is then used to cut the carbon tubes, which are at the microscale, into fragments ranging from 100 to 500 nanometers in size ； Secondly, by employing chemical modification combined with ultrasound technology, it was successfully achieved to carry out efficient (greater than 75%) controlled assembly of certain metal and metal oxide nanoparticles within carbon tubes, with controllable particle sizes. Some of the research results were published in the Journal of the American Chemical Society (Chen Wei, Bao Xinhe et al., JACS, 2006).