The corresponding mesh
structure is shown in Figure 6b, with the first melted segment marked by a red cross symbol. Figure 6 Starting point of melting of the Ag nanowire mesh. (a) Temperature profile and (b) mesh structure. Subsequently, the mesh structure undergoes a process of the consecutive melting of large BI2536 numbers of individual nanowires. During the melting of the mesh as shown in Figure 5a, the variation in I m and V m of the mesh exhibits the repetition of three different CB-839 in vitro trends: (I) both I m and V m decrease, (II) both I m and V m increase, and (III) I m decreases while V m increases. The solid-line arrows in Figure 5c,d indicate these three trends. Such repetition of zigzag pattern as shown in Figure 5a can be explained in detail as below. After one mesh segment is melted, the electrical GDC-0973 nmr pathway in the mesh is changed so that the mesh resistance increases, and therefore Joule heating increases. In one case, the maximum temperature of the mesh may be far beyond the melting point of the wire, which means the present current is much higher than that for the subsequent wire melting. To precisely obtain the melting current for the subsequent wire melting
(i.e., the current when the maximum temperature of the mesh properly reaches the melting point), the input current has to be decreased, which means the decrease of melting current. In another case, the maximum temperature of the mesh is still lower than the melting point of the wire. To make further melting, very the input current has to be increased to make the maximum temperature rise up to the melting point, which implies the increase of melting current. The irregular alternation of these two cases leads to the zigzag pattern of the relationship between I m and V m during the melting process of the mesh. Moreover, it is thought that if the pitch size of the mesh is smaller, the extent of zigzag pattern will be mitigated. In an extreme case, when the pitch size is zero which makes the mesh transit to thin film, the present zigzag pattern will be diminished and the relationship between I m and V m will become smooth. It is clear
that there is a sudden sharp decrease in both I m and V m during the melting process (marked by an ellipse in Figure 5a), accompanied by a doubling of R (marked by an ellipse in Figure 5b). Although three segments melt simultaneously (marked by red cross symbols in Figure 7a), it is believed that the breakage of the segment located on the lower boundary of the mesh plays the key role by resulting in the detour of the current. Figure 7 Melting process of the Ag nanowire mesh. (a) Mesh structure at the sudden fall of melting current and (b) mesh structure at the melting endpoint. Finally, the mesh becomes open when two segments, marked by red cross symbols in Figure 7b, melt. Obviously, the broken mesh segments are sufficient to eliminate the continuous electrical pathway across the mesh.