Photodetectors (PDs) are essential components in modern optoelectronics, converting light into electrical signals for applications such as imaging, environmental monitoring, optical communications, and wearable sensors. Their performance is evaluated by metrics like responsivity, detectivity, response speed, and stability. Achieving high performance while maintaining scalability, flexibility, and cost-efficiency remains a major challenge for next-generation devices [1].

Halide perovskites have emerged as highly promising photoactive materials. They offer tunable bandgaps, strong optical absorption, long carrier diffusion lengths, low trap densities, and good thermal and ambient stability [2]. These properties enable efficient light harvesting and broad spectral detection. Furthermore, perovskites can be engineered into “raisin bread” architectures, where high-quality perovskite grains are embedded in a secondary phase. This two-phase system not only improves charge transport and broadens the spectral response but also enhances the structural and environmental stability of the perovskite layer, making devices more robust under operational conditions. However, their relatively low charge carrier mobility in thin films, limited by grain boundaries and defects, restricts photoconductive gain and overall device responsivity.

Graphene, a two-dimensional carbon material with exceptional carrier mobility (~40,000 cm²·V⁻¹·s⁻¹),can address this limitation [4]. Although its intrinsic light absorption is low (~2.6%), its ultrafast charge transport makes it an ideal partner for perovskite-based photodetectors. By forming graphene-perovskite hybrids, one can achieve efficient charge extraction, and significantly enhance gain and responsivity.

These hybrid devices exhibit remarkable performance, including broadband photodetection, high responsivity exceeding 57,000 A/W excellent repeatability over multiple on/off cycles, and long-term operational stability in ambient conditions for over six months. Moreover, maskless, vacuum-free inkjet printing allows direct deposition of perovskites onto graphene, supporting flexible substrates and scalable fabrication [5,6].

Graphene-perovskite hybrid photodetectors thus combine the best of both materials, offering a versatile, high-performance platform for next-generation optoelectronic systems. Their potential spans wearable devices, artificial vision, environmental sensing, and other applications requiring sensitive, fast, and reliable light detection.