Flexible Photodetectors with High Responsivity and Broad Spectral Response Employing Ternary Sn<sub><i>x</i></sub>Cd<sub>1–<i>x</i></sub>S Micronanostructures
Muhammad Zubair Nawaz, Xu Liu, Xing Zhou, Khizar Hussain Shah, Muhammad Yaqub, Jiale Wang, B. H. Wu, Chunrui Wang
Abstract
Ultrasensitive, fast response, and broad spectral response flexible photodetectors (FPDs) would be desirable for advanced technology. Here, high purity tin cadmium sulfide (SnxCd1–xS) micronanostructures (nanobelts, tapered nanobelts with/without hexagonal tips, nanorods, nanocombs, and nanoflowers) were grown via a facile one-step chemical vapor deposition (CVD) route and utilized for fabrication of metal–semiconductor–metal (MSM) rigid/flexible nanodevices. Compared to pristine CdS nanobelts, the Raman spectrum of SnxCd1–xS nanobelts exhibits a 3 cm–1 red shift at room temperature. The temperature-dependent intensity ratio (I2LO/I1LO) varies from 1.21 to 1.89, reflecting improved electron–lattice interaction in the SnxCd1–xS nanobelts. In addition, a ternary nanobelt based rigid device sensitively responds to UV-Vis light with high responsivity (4.82 × 101 A/W), high external quantum efficiency (1.46 × 104%), and fast response speed (20 ms). Compared to pristine CdS nanobelt devices, it responds to a broader spectral range while maintaining outstanding photoconductive characteristics. Additionally, SnxCd1–xS nanobelt FPDs exhibited good mechanical and electrical stabilities with a performance comparable to those of rigid devices. The result indicates that the ternary SnxCd1–xS micronanostructures may be an excellent candidate to enhance the optoelectronic performances of micro/nanodevices.