流体排布与介电电泳结合排列组装碳纳米管

Combining Fluidic Alignment with Dielectrophoresis to Assemble Carbon Nanotubes

流体排布和介电电泳是碳纳米管生长后排列组装的两种方法.流体排布可实现基片上较大范围的碳纳米管定向排列,且流体剪切力作用可将弯曲的碳纳米管在一定程度上拉直,但利用流体难以实现在特定位置组装碳纳米管.而介电电泳通过电极上不均匀电场实现碳纳米管在电极间沿电场方向的定向定位排列组装,介电电泳的不足之处在于电泳力难以将弯曲的碳纳米管拉直.本研究结合这两种组装方法的优势,采用流体与介电电泳结合排列组装碳纳米管.通过选择流体流动和电泳参数,流体结合直流或带直流偏置的交流电泳实现了较好的碳纳米管排列组装.与介电电泳组装相比,结合流体能减少碳纳米管之间的粘连,起到梳理拉直的作用,并提高了组装效率;与流体排布相比,结合介电电泳实现了碳纳米管在指定位置的组装.

Fluidic alignment and dielectrophoresis（DEP） are both methods of assembling carbon nanotubes（CNTs）.Fluidic alignment can facilitate directional alignment of CNTs on a larger area of the substrate and curly CNTs can be straightened to a certain extent by the fluidic shear stress,yet it is difficult to assemble CNTs in appointed positions with fluidic alignment.With the uneven electric field on electrodes,DEP can assemble CNTs in appointed positions along the direction of electric field between electrodes but cannot straighten curly CNTs.A new method for CNTs assembly which combined fluidic alignment with DEP was proposed in this paper,which achieved good CNTs assembly with the choice of fluidic and DEP parameters and combination of fluidic alignment with DC or AC plus DC DEP.Compared with assembly with only DEP,combination with fluidic alignment can prevent adherence between CNTs and straighten CNTs,so that assembly efficiency is enhanced.Compared with fluidic alignment,combination with DEP can achieve assembly of CNTs in appointed positions.