CTS Quantum Dots–ZnO Nanocomposites for Broadband Photodetection

This paper reports the fabrication of a high-performance and broadband photodetector based on the Cu2SnS3 (CTS) quantum dots (QDs)/ZnO hybrid structure on ITO glass. The enhanced performance and a broad-spectrum photodetector have been achieved for this hybrid structure compared with any single-material-based device. The visible–near-infrared (NIR)-sensitive capabilities of CTS QDs have been combined with UV-sensitive ZnO thin films for broadband operation. The heterostructure device has been fabricated by simple drop-casting of CTS QDs on low-cost spin-coated ZnO thin films on the ITO substrate. The fabricated device possesses good photoresponse properties (sensitivity, responsivity) from the visible to NIR spectrum. The resultant responsivity of the CTS QDs/ZnO/ITO photodetector measured under UV (@360 nm), visible (@720 nm), and NIR (@1050 nm) illuminations has been found to be ∼2.8, ∼0.2, and ∼0.4 (A/W), respectively, at 2.5 V. The designed hybrid device may provide a competitive wideband photodetector having merits of low cost and a simple fabrication structure.