Carbon nanotubes (CNT) have been widely used as catalyst supports, and the confinement of metal nanoparticles inside the CNT cavity have received much attention. In this study, graphitic carbon nitride were used to introduce nitrogen to CNT and form ruthenium nanoparticles inside the CNT channel. The XPS evidenced that the ruthenium nanoparticles in the CNT cavity are present in more reduced state, and the nitrogen species are in a pyridinic and a pyrrolic form. The prepared catalysts exhibited excellent hydrogen and carbon monoxide selectivity. The hydrogen-to-carbon monoxide ratio was close to the stoichiometric ratio of methanol decomposition. In contrast, the ruthenium nanoparticles outside the CNT showed lower carbon monoxide selectivity at high methanol conversion. The alteration of electrical properties of ruthenium nanoparticles by the CNT channel and N-doping might hamper side reactions, such as water gas shift, methanation, dimethyl ether formation upon methanol decomposition.

中文翻译：

---

Ru纳米粒子在碳纳米管内的限制：对甲醇分解的选择性控制

碳纳米管 (CNT) 已被广泛用作催化剂载体，并且将金属纳米粒子限制在 CNT 腔内受到了广泛关注。在这项研究中，石墨氮化碳用于将氮引入 CNT 并在 CNT 通道内形成钌纳米颗粒。XPS 证明 CNT 腔中的钌纳米颗粒以更多还原状态存在，并且氮物质以吡啶和吡咯形式存在。制备的催化剂表现出优异的氢气和一氧化碳选择性。氢与一氧化碳之比接近甲醇分解的化学计量比。相比之下，CNT 外的钌纳米颗粒在高甲醇转化率下表现出较低的一氧化碳选择性。