Protected catalyst growth of graphene and carbon nanotubes

Low temperature growth of carbon nanotubes – A review

“…PECVD strategies are: choice of Carbon feedstock [147], solution processed catalyst [159], multilayered catalyst [157], size-classified catalyst [138], support layer [137], Oxidative dehydrogenation [156], remote plasma [100,139] and pulse power [141,153]. PTCVD strategies are: support layer [79], carbon source [77], rapid-growth process [60], maximizing energy coupling by optimising underlayers [79] and protected catalyst method [56]. some engineering solutions of achieving low temperature growth of CNTs which includes the use of a multi-zone CVD system and the PTCVD system.…”

“…2014: Roll to roll production of CNTs (reprinted with permission from Elsevier, Copyright 2014 [55]). 2019: Protected catalyst method for the growth of CNTs and graphene (reprinted with permission from Elsevier, Copyright 2019 [56]). (A colour version of this figure can be viewed online.)…”

“…SEM is mainly used to observe length of CNTs, orientation and to estimate their density but it is unable to give accurate information about the diameter, walls, chirality and structural quality. STM allows to determine diameter and chirality of individual tubes whereas TEM is used to find number of walls, diameter and structural quality of CNTs but both of these tools are inefficient because of their operating conditions and sample preparation requirements [56,112].…”

“…The growth window for m-CNT is found to be wider than for s-CNTs, and the smaller acetylene ratio (<10%) favors the growth of s-CNTs but the higher ratio (>10%) favors the growth of m-CNTs. Recently, we introduced a novel 'protected catalyst method' for the low temperature growth of CNTs and graphene [56]. The method involves capping the catalyst with a layer of a suitable material, e.g.…”

Low-Cost Catalyst Ink for Simple Patterning and Growth of High-Quality Single- and Double-Walled Carbon Nanotubes

“…Further issues occur after the catalyst has been deposited on the substrate, as it can be easily contaminated (poisoned) during transportation between the sputter coater and the CVD growth equipment, preventing or limiting growth. This leads to a requirement for additional processing steps to add a protection layer to the catalyst, protecting it from environmental contaminants such as oxidation, etchant attack, and moisture . Although a proven method to fabricate high-quality CNT devices, the slow, labor-intensive, and expensive nature of this technique means that few devices are manufactured this way; unless they are small enough that numerous devices can be achieved on one large wafer, such as transistors or microcontactors …”