Solution‐Processed Transparent Self‐Powered p‐CuS‐ZnS/n‐ZnO UV Photodiode

Abstract

Transparent diodes formed by a heterojunction between p-type CuS-ZnS and n-type ZnO thin films were fabricated by sequential chemical bath deposition and sol-gel spin coating. The diodes are transparent in the visible (%70% at 550 nm) and exhibit a good rectifying characteristics, with I f /I r ratios of up to 800 at AE1 V, higher than most of the reported solution-processed diodes measured at a similar bias. More importantly, when operated as a selfpowered (zero bias) UV photodetector, they show stable and fast (<1 s) photoresponse with a maximum responsivity of 12 mA W À1 at 300 nm. Both the response time and responsivity of the p-CuZnS/n-ZnO UV photodiode are comparable or superior to similar solution-processed devices reported in the literature.

Tunable self‐powered n‐SrTiO3 photodetectors based on varying CuS‐ZnS nanocomposite film (p‐CuZnS, p‐CuS, and n‐ZnS)

“…We demonstrated that the hole conductivity can be achieved as high as 1000 S cm –1 , and the film transparency can be tailored by adjusting the concentration of the complexing agents which can reach up to 70% in the visible range of the spectrum. Xu et al fabricated the p‐CuS‐ZnS (p‐CZS)/n‐ZnO UV photodiode with a good rectifying characteristics and a self‐powered feature, which showed stable and fast photoresponse . Meanwhile, we demonstrated the successful fabrication of a novel wearable self‐powered p‐CZS/n‐TiO 2 UV device with high performance .…”

“…In addition, this CZS composite film can be grown in situ on various substrates (quartz, silicon, etc.) or other semiconductor materials to construct heterojunctions via facile solution process …”

“…It also has a good spectral selectivity. The STO single crystal has an excellent stability, and the CZS film has also shown a good stability (<300°C) . Therefore, the p‐CZS/n‐STO photodetector with high performance can be maintained for several months in the surrounding environment.…”

“…or other semiconductor materials to construct heterojunctions via facile solution process. [37][38][39] Figure 2A demonstrates the X-ray diffraction (XRD) pattern of the STO crystal film. The diffraction peak for the STO crystal appearing at 22.8 and 46.5 are assigned to (100) and (200) crystal planes of cubic strontium titanate (JCPDF no.…”

“…Xu et al fabricated the p-CuS-ZnS (p-CZS)/n-ZnO UV photodiode with a good rectifying characteristics and a self-powered feature, which showed stable and fast photoresponse. 38 Meanwhile, we demonstrated the successful fabrication of a novel wearable self-powered p-CZS/n-TiO 2 UV device with high performance. 39 The fiber-shaped device shows an outstanding responsivity and high photocurrent.…”