Bi2Te3/Bi2Se3/Bi2S3 Cascade Heterostructure for Fast‐Response and High‐Photoresponsivity Photodetector and High‐Efficiency Water Splitting with a Small Bias Voltage

• DOI: 10.1002/advs.202205460
• Publication Date: 2022-12-27T19:00:23Z
• Authors: Chunhui Lu; Mingwei Luo; Wen Dong; Yanqing Ge; Taotao Han; Yuqi Liu; Xinyi Xue; Nan Ma; Yuanyuan Huang; Yixuan Zhou; Xinlong Xu
• Keywords: Bismuth; Quantum Efficiency; Specific detectivity

Large-scale multi-heterostructure and optimal band alignment are significantly challenging but vital for photoelectrochemical (PEC)-type photodetector water splitting. Herein, the centimeter-scale bismuth chalcogenides-based cascade heterostructure is successfully synthesized by a sequential vapor phase deposition method. The multi-staggered of Bi2 Te3 /Bi2 Se3 S3 optimized verified X-ray photoelectron spectroscopy. PEC photodetectors based on these heterostructures demonstrate highest photoresponsivity (103 mA W-1 at -0.1 V 3.5 mAW-1 0 under 475 nm light excitation) among previous reports two-dimensional materials related heterostructures. Furthermore, display fast response (≈8 ms), high detectivity (8.96 × 109 Jones), external quantum efficiency (26.17%), incident photon-to-current (27.04%) nm. Due to rapid charge transport efficient absorption, demonstrates highly hydrogen production rate (≈0.416 mmol cm-2 h-1 ≈14.320 µmol with or without sacrificial agent, respectively), which far superior those pure chalcogenides its type-II large-scale offers an innovative method improve performance optoelectronic devices in future.