Metal work function enabled modulation on photo-detective properties for flexible Cu_2CoSnS_4 films with different annealing time

摘要

Herein, direct solution spin coating-based earth-abundant quaternary Cu2CoSnS4 films are reported to achieve cost-effective, visible photodetectors on flexible polyimide (PI) substrates. Different annealing times and metal work functions effectively control the optoelectronic properties of flexible CCTS films. Furthermore, the photosensitivity (50 +/- 4), photoresponsivity ((1090 +/- 15) mA/W), and specific detectivity ((2.38 +/- 0.21) x 10(10) Jones) are exhibited for CCTS photodetectors with Au electrodes, along with composition ratio of (Cu/(Co + Sn) = 0.88) and 400 degrees C for 2 h condition. This implies that understanding process conditions and their mechanism can be beneficial for securing high-performance, flexible, visible photodetectors.