Flexible self-powered photoelectrochemical-type photodetectors based on Bi2O2S/GO composites

Flexible photodetectors (PDs) have attracted great attention in the fields of environmental monitoring, image sensing and self-powered integrated electronic devices due to their advantages of wearability and bendability. Therefore, in this work a photoelectrochemical (PEC) photodetector was constructed based on a quasi-solid-state electrolyte and a bismuth oxysulfide (Bi2O2S)/graphene oxide (GO) composite structure. This detector was fabricated using a simple method, and was more convenient to use than a liquid electrolyte-based photodetector. Moreover, compared with the single Bi2O2S nanosheets, the composite material exhibited more excellent self-powered ability and mechanical performance. The photoelectrochemical test showed that under 0 V bias voltage, the photocurrent density of the composite material reached 4 μA cm−2, which was about 6 times that of the single material. In addition, after bending at different angles for 1000 seconds, the photocurrent of the Bi2O2S/GO photodetector based on the quasi-solid-state electrolyte hardly decayed. The results show that the flexible photoelectrochemical photodetector based on Bi2O2S/GO exhibits robust photoelectric performance even under bending conditions, and demonstrates excellent stability in long-term photocurrent tests. Therefore, Bi2O2S/GO is a candidate material with excellent performance and great application potential in the photodetector field.