Bharti Yugam, Malik Vikas, Bhandari Preeti, Aggarwal Shruti
USBAS,Guru Gobind Singh Indraprastha University, Dwarka, Delhi 110078, India.
Department of Physics and Material Science & Engineering, Jaypee Institute of Information Technology, Noida 201304, India.
Nanotechnology. 2024 Oct 14;36(1). doi: 10.1088/1361-6528/ad8166.
We have studied the impact of nanowire alignment and measurement direction at the percolation threshold on the effective resistance () of two-dimensional (2D) films. This helps us to analyze the effect of anisotropy on the conductivity and transmittance of the nanowire-based network characterized by the disorder parameter (). These optoelectronic properties are determined for systems with monodisperse and bimodal length distribution (a combination of two fixed lengths of nanowires). The 2D systems simulated using our computational approach are assumed to be transparent and conductive in which percolative transport is the primary conduction mechanism. We obtain our results numerically using a computational and geometrical approach, i.e. a Discrete (grid) method that is advantageous in algorithm speed. For a particular disorder parameter, the conductivity and transmittance increase as the length fraction () increases for the bimodal distribution of the length of nanowires in networks. We have observed the maximum conductivity when the nanowires are highly aligned along the measurement direction of percolation, in contrast to the isotropic arrangement of nanowires. Significantly, alignment introduced in nanowires leads to a higher percolation threshold which leads to a decrease in the transmittance of the network. We show that the resistivity of the monodisperse network in the direction parallel (perpendicular) to the alignment decreases (increases) with the disorder parameter and scales as(). This scaling holds true for the bimodal distribution of nanowires as well. For a particular, the electrical anisotropy increases with. The anisotropy is maximum for nearly aligned nanowires in a bimodal network with the highest proportion of the longest wire considered. For the maximally aligned wires and highest, we obtained an approximately 50%enhancement in the figure of merit, denoted by. Hence, incorporating longer-length wires and increasing the alignment in nanowire networks can increase the conductivity, anisotropy, and figure of merit which may benefit a vast range of applications.
我们研究了在渗流阈值下纳米线排列和测量方向对二维（2D）薄膜有效电阻（）的影响。这有助于我们分析各向异性对以无序参数（）为特征的基于纳米线的网络的电导率和透射率的影响。这些光电特性是针对具有单分散和双峰长度分布（两种固定长度纳米线的组合）的系统确定的。使用我们的计算方法模拟的二维系统被假定为透明且导电，其中渗流传输是主要的传导机制。我们使用一种计算和几何方法，即离散（网格）方法，通过数值计算得到结果，该方法在算法速度方面具有优势。对于特定的无序参数，在网络中纳米线长度的双峰分布情况下，随着长度分数（）增加，电导率和透射率也会增加。与纳米线的各向同性排列相反，当纳米线沿渗流测量方向高度排列时，我们观察到了最大电导率。值得注意的是，纳米线中引入的排列会导致更高的渗流阈值，进而导致网络透射率降低。我们表明，单分散网络在平行（垂直）于排列方向的电阻率随无序参数降低（增加），且按（）缩放。这种缩放对于纳米线的双峰分布也成立。对于特定的，电各向异性随增加。在考虑最长线比例最高的双峰网络中，对于几乎排列的纳米线，各向异性最大。对于排列最整齐的线和最高的，我们得到了优值大约50%的提高，用表示。因此，在纳米线网络中加入更长的线并增加排列可以提高电导率、各向异性和优值，这可能有利于广泛的应用。
