High-Performance Inorganic Perovskite Quantum Dot–Organic Semiconductor Hybrid Phototransistors

Abstract

All-inorganic lead halide perovskite quantum dots (IHP QDs) have great potentials in photodetectors. However, the photoresponsivity is limited by the low charge transport efficiency of the IHP QD layers. High-performance phototransistors based on IHP QDs hybridized with organic semiconductors (OSCs) are developed. The smooth surface of IHP QD layers ensures ordered packing of the OSC molecules above them. The OSCs significantly improve the transportation of the photoexcited charges, and the gate effect of the transistor structure significantly enhances the photoresponsivity while simultaneously maintaining high I_photo/I_dark ratio. The devices exhibit outstanding optoelectronic properties in terms of photoresponsivity (1.7 × 10⁴ A W⁻¹), detectivity (2.0 × 10¹⁴ Jones), external quantum efficiency (67000%), I_photo/I_dark ratio (8.1 × 10⁴), and stability (100 d in air). The overall performances of our devices are superior to state-of-the-art IHP photodetectors. The strategy utilized here is general and can be easily applied to many other perovskite photodetectors.

High-performance hybrid phototransistors based on all-inorganic lead halide perovskite quantum dots and organic semiconductors are fabricated and characterized. Because of the outstanding properties of materials, the gate-tunable phototransistors exhibit significantly high performance, including photoresponsivity (≈1.7 × 10⁴ A W⁻¹), detectivity (≈2.0 × 10¹⁴ Jones), EQE (≈67000%), I_photo/I_dark ratio (≈8.1 × 10⁴), and long-term stability in air.

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