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

Abstract

In this letter, ultra-wide-bandgap Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> as the interlayer is grown by mist chemical vapor deposition (mist-CVD) between perovskite and TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> electron transport layer in perovskite photodetectors (PDs). To get a stable working condition and low-cost fabrication, all-inorganic CsPbIBr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> is adopted and the expensive vacuum-deposited metal electrode is replaced by printing carbon paste. The vacuum-free, self-powered CsPbIBr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> PD with Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> interlayer achieves an obviously improved performance, with a low dark current of 4.15 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-9</sup> A, high responsibility of 0.22 A/W, fast response time of 1.83μs, and high peak specific detectivity of 1.83×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sup> Jones. This work provides a strategy to develop high-performance self-powered PDs with the ultra-wide-bandgap Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> interlayer and a reduced cost.