Towards a better understanding of FC-CVD carbon nanotube synthesis

碳纳米管（CNTs）是一种令人兴奋的材料，由于其独特的电学、热学和力学性能。浮动催化剂化学气相沉积（FC-CVD）碳纳米管合成工艺允许连续生产碳纳米管气凝胶。这些气凝胶可以直接从反应器中收集，作为纤维和垫，用于一系列应用。自2004年在剑桥发明以来，人们对FC-CVD工艺进行了深入研究，从而在理解该工艺背后的物理机制方面取得了突破。这些研究依赖于提取测量，但这种技术的局限性在我们对这一过程的理解中留下了盲点。我的目标是开发一种光学透明的FC-CVD反应器，能够进行现场拉曼，FTIR和其他过程的测量。这将允许对FC-CVD生长过程进行更详细的研究，特别是关于不能用萃取技术测量的短寿命自由基物种的性质。该项目与EPSRC的能源、脱碳和工程主题紧密相关。碳纳米管以其独特的材料特性成为人类制造的前沿，这些特性使碳纳米管具有解锁新技术和工程能力的潜力。然而，在FC-CVD反应器中碳纳米管的合成尚不完全清楚，因此很难将该工艺扩大到工业规模，同时提供商业成功所需的效率。通过提高我们对碳纳米管合成的FC-CVD工艺的理解，我的目标是能够设计出更高效的反应器。此外，我们的工艺将甲烷转化为固体碳（cnt）和氢，后者可用于工业过程和清洁能源等应用。这个过程的二氧化碳强度比蒸汽甲烷重整低得多，蒸汽甲烷重整是当今最常见的制氢方法。

Carbon nanotubes (CNTs) are an exciting material due to their exception electrical, thermal, and mechanical properties. The floating catalyst chemical vapour deposition (FC-CVD) process for CNT synthesis allows the continuous production of CNT aerogels. These aerogels can be collected directly from the reactor as fibres and mats for use in a range of applications. Since its invention in Cambridge in 2004, the FC-CVD process has been intensively researched leading to breakthroughs in understanding of the physical mechanisms underlying the process. These studies have relied on extractive measurements, but the limitations of such techniques leave blind spots in our understanding of the process. I aim to develop an optically transparent FC-CVD reactor capable of performing in-situ Raman, FTIR and other measurements of the process. This will allow a more detailed study of the FC-CVD growth process, especially regarding the nature of short-lived radical species that cannot be measured using extractive techniques. This project sits firmly within the EPSRC's themes of energy and decarbonisation, and engineering. Carbon nanotubes are the frontier of what humans can make in terms of their exceptional material properties, these properties give CNTs the potential to unlock new technological and engineering capabilities. However, the synthesis of CNTs in FC-CVD reactors is not fully understood, making it difficult to scale the process up to industrial scales while providing the efficiency needed for commercial success. By improving our understanding of the FC-CVD process for CNT synthesis, I aim to enable the design of more efficient reactors. Additionally, our process converts methane into solid carbon (CNTs) and hydrogen, the latter can then be used in applications such as industrial processes and clean energy. This process has a much lower CO2 intensity than steam methane reforming, the most common method of hydrogen production today.