Abstract The present study introduces a process to grow micro-honeycomb (µ-HC) vertically aligned carbon nanotubes (VACNTs) using thermal chemical vapor deposition technique. Methane is used as a source of carbon and hydrogen gas as a reducing agent. Where, the fabricated µ-HC structure reported in literature involves complex synthesis process and requires a catalyst layer, the novelty of the process used here lies in the fact that no catalyst layer is used for the growth of CNT network, rather copper foil is used as a substrate. The in-situ cracking of CNTs due to water treatment leads to the formation of µ-HC CNT network, which is confirmed by Raman spectroscopy. Further scanning electron microscopy analysis shows that the length of developed µ-HC CNT is ∼5 µm. Hexagonal µ-HC network shows more than 94% absorption in UV-Vis-NIR wavelength region. The designed process provides high-yield with a low-cost synthesis of vertically aligned CNTs having 3 D microarchitecture. The fabricated CNT network can be used as an electrode for supercapacitor, as an active layer in a photovoltaic cell and most of the energy harvesting devices.

中文翻译：

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用于能量收集的 VACNT 的无催化生长

摘要 本研究介绍了一种使用热化学气相沉积技术生长微型蜂窝 (μ-HC) 垂直排列的碳纳米管 (VACNT) 的过程。甲烷用作碳源，氢气用作还原剂。在文献中报道的制造的 μ-HC 结构涉及复杂的合成过程并需要催化剂层，这里使用的工艺的新颖之处在于没有催化剂层用于 CNT 网络的生长，而是使用铜箔作为基材。由于水处理导致 CNT 的原位裂解导致 μ-HC CNT 网络的形成，拉曼光谱证实了这一点。进一步的扫描电子显微镜分析表明，开发的 µ-HC CNT 的长度为 ~5 µm。六边形 µ-HC 网络在 UV-Vis-NIR 波长区域显示出超过 94% 的吸收。所设计的工艺以低成本合成具有 3D 微结构的垂直排列的碳纳米管提供了高产量。所制造的 CNT 网络可用作超级电容器的电极、光伏电池和大多数能量收集装置中的活性层。