High-Performance, Vacuum-Free, and Self-Powered CsPbIBr₂ Photodetectors Boosted by Ultra-Wide-Bandgap Ga₂O₃ Interlayer

In this letter, ultra-wide-bandgap Ga2O3 as the interlayer is grown by mist chemical vapor deposition (mist-CVD) between perovskite and TiO2 electron transport layer in perovskite photodetectors (PDs). To get a stable working condition and low-cost fabrication, all-inorganic CsPbIBr2 is adopted and the expensive vacuum-deposited metal electrode is replaced by printing carbon paste. The vacuum-free, self-powered CsPbIBr2 PD with Ga2O3 interlayer achieves an obviously improved performance, with a low dark current of 4.15 x 10(-9) A, high responsibility of 0.22 A/W, fast response time of 1.83 mu s, and high peak specific detectivity of 1.83x10(12) Jones. This work provides a strategy to develop high-performance self-powered PDs with the ultra-wide-bandgap Ga2O3 interlayer and a reduced cost.