Twin-Related Branching of Solution-Grown ZnSe Nanowires

ZnSe nanowires were grown by the solution−liquid−solid mechanism at 350 °C in either trioctylamine (TOA) or trioctylphosphine oxide (TOPO) using bismuth nanocrystals as seeds. Approximately half of the nanowires produced in TOA had short ZnSe branches off their sidewall surfaces, whereas nanowires grown in TOPO did not exhibit branching. The ZnSe nanowires with branching grew predominantly in the <112> direction with a large number of {111} twins extending down their length. The branches grew epitaxially from the sidewall surface in the <111> direction with a large concentration of lamellar {111} twins. The absence of sidewall nucleation and branching from ZnSe nanowires grown in TOPO can be explained by the stronger surface passivation from TOPO relative to that of TOA.