Rational design of comb-like 1D–1D ZnO–ZnSe heterostructures toward their excellent performance in flexible photodetectors†
Abstract
One-dimensional (1D) Zn-based heterostructures have attracted considerable interest in the field of photodetection because of their tunable properties, flexibility, and unique optoelectronic properties. However, designing 1D multi-component Zn-based heterostructures for advanced photodetectors is still a great challenge. Herein, comb-like 1D–1D ZnO–ZnSe heterostructures with ZnO and ZnSe nanowires (NWs) comprising the shaft and teeth of a comb are reported. The length of the ZnO NWs can be modulated in the range of 300–1200 nm. Microstructural characterizations confirm that the 1D heterostructure clearly shows the spatial distribution of individual components. The well-designed structure displays an extended broadband photoresponse and higher photosensitivity than pure ZnSe NWs. Furthermore, ZnSe NWs with an appropriate length of ZnO branches show increased photoresponses of 3835% and 798% compared to those of pure ZnSe NWs under green and red-light irradiation, respectively. In addition, the integrated flexible photodetector presents excellent folding endurance after 1000 bending tests. This well-designed structure has significant potential for other 1D-based semiconductors in optoelectronic applications.