For the high-temperature catalytic reaction, revealing the interface of catalyst–support and its evolution under reactive conditions is of crucial importance for understanding the reaction mechanism. However, much less is known about the atomic-scale interface of the hard-to-reduce silica-metal compared to that of reducible oxide systems. Here we reported the general behaviors of SiO₂ migration onto various metal (Pt, Co, Rh, Pd, Ru, and Ni) nanocrystals supported on silica. Typically, the Pt/SiO₂ catalytic system, which boosted the CO₂ hydrogenation to CO, exhibited the reduction of Si⁰ at the Pt-SiO₂ interface under H₂ and further Si diffusion into the near surface of Pt nanoparticles, which was unveiled by in-situ environmental transmission electron microscopy coupled with spectroscopies. This reconstructed interface with Si diffused into Pt increased the sinter resistance of catalyst and thus improved the catalytic stability. The morphology of metal nanoparticles with SiO₂ overlayer were dynamically evolved under reducing, vacuum, and oxidizing atmospheres, with a thicker SiO₂ layer under oxidizing condition. The theoretical calculations revealed the mechanism that the Si-Pt surface provided synergistic sites for the activation of CO₂/H₂ to produce CO with lower energy barriers, consequently boosting the high-temperature reverse water-gas shift reaction. These findings deepen the understanding toward the interface structure of inert oxide supported catalysts.

Carbon nanotubes (CNTs) have attracted great attentions in the field of electronics, sensors, healthcare, and energy conversion. Such emerging applications have driven the carbon nanotube research in a rapid fashion. Indeed, the structure control over CNTs has inspired an intensive research vortex due to the high promises in electronic and optical device applications. Here, this in-depth review is anticipated to provide insights into the controllable synthesis and applications of high-quality CNTs. First, the general synthesis and post-purification of CNTs are briefly discussed. Then, the state-of-the-art electronic device applications are discussed, including field-effect transistors, gas sensors, DNA biosensors, and pressure gauges. Besides, the optical sensors are delivered based on the photoluminescence. In addition, energy applications of CNTs are discussed such as thermoelectric energy generators. Eventually, future opportunities are proposed for the Internet of Things (IoT) oriented sensors, data processing, and artificial intelligence.