Ag2Se micropatterns via viscoelastic flow-driven phase separation

Abstract

A novel approach to prepare micropatterns of metal chalcogenides is proposed by employing viscoelastic flow-driven patterning. A consecutive process involving deposition of the Se precursor on a pattern of a crystalline polymer, chemical reduction of the precursor into amorphous Se (a-Se), and short-time thermal annealing above the melting temperature of the patterned polymer generated regular patterns of a-Se. This work demonstrates patterns of periodic lines and circles which is driven by the viscoelastic polymer flow and the phase separation of Se from the polymer. Additional thermal annealing facilitated the lateral growth of trigonal-Se (t-Se) nanowires from the Se patterns. The growing t-Se nanowires eventually meet each other to produce a 2D network structure. Chemical transformation of the Se into Ag₂Se generated metal chalcogenide network structures.