Infrared photodetectors play an essential role in diverse military and civilian applications. Nevertheless, traditional infrared detection materials often suffer from inherent limitations, such as fixed bandgaps and stringent low-temperature operational requirements. The emergence of two-dimensional (2D) materials has revolutionized infrared detection technology, enabling the development of efficient room-temperature photodetectors. Among various 2D materials, black phosphorus (BP) has attracted considerable attention due to its narrow direct bandgap, tunable electronic properties, and exceptional hole mobility. These unique attributes endow BP-based infrared photodetectors with superior performance, including ultrafast response times, broad detection spectral ranges, and remarkably low dark currents. This review systematically summarizes recent advancements in material synthesis techniques, underlying device principles, and performance optimization strategies of BP infrared photodetectors. Additionally, it critically addresses ongoing challenges and offers a comprehensive perspective, laying a solid theoretical foundation and practical roadmap for advancing next-generation high-performance infrared photodetection technologies.

The widespread proliferation of modern wireless devices coupled with overlapping power emissions has brought about electromagnetic (EM) pollution issues, posing many challenges to environment and human health. Therefore, the development of EM shielding devices with high green shielding index (g_s) is essential, as they offer absorption-dominant protection that minimizes reflections and safeguards both health and electronics. MXene, with its intrinsic ultra-high electrical conductivity, liquid-phase tunable surface chemistry, low density, large specific surface area, thermal stability, and mechanical stability, has become the leading two-dimensional (2D) material driving the development of green EM shielding devices. In this review we emphasize device-level strategies with engineered architectures for MXene-based green EM shielding. We first examine MXene’s crystal and electronic structure and the fundamental attenuation mechanisms in MXene-based devices. Then we survey fabrication and assembly methods, analyzing three device-level strategies for MXene-based green EM shielded devices: 3D architectures, meta-structure/meta-surfaces, and external stimulus. Throughout, we highlight how MXene’s distinguished properties enable green EM interference (EMI) shielding devices that minimize secondary interference. Finally, we discuss the challenges faced in the effective utilization of MXene-based in green EM shielding devices, provide insights into these challenges, and offer guidelines for developing the solutions of next-generation green MXene-based EM shielding devices.