Cu 2 S nanowires and MnS/Cu 2 S nanojunctions derived from γ‐MnS nanowires via selective cation‐exchange reaction

Cu 2 S nanowires and MnS/Cu 2 S junctions have been derived on the basis of γ‐MnS nanowires via cation‐exchange reaction. Relationships between a selective cation exchange and the growth direction of the γ‐MnS nanowires are identified by means of transmission electron microscopy. In the case of γ‐MnS nanowires with [0001] growth direction, Cu + exchange with an initial γ‐MnS nanowire results in a Cu 2 S nanowire. In contrast, for γ‐MnS nanowires with [1–100] growth direction, Cu + exchange leads to a striped MnS/Cu 2 S junction. Mechanisms for this selective cation exchange are proposed.