Progress on self-powered photodetectors based on low-dimensional materials

In recent years, there has been a growing interest in self-powered photodetectors, which can detect light without needing an external power supply. This unique feature makes them highly attractive for addressing the current energy shortage and the future demand for miniaturized devices. Among various design approaches for self-powered photodetectors, the use of low-dimensional materials holds great promise. Low-dimensional nanomaterials offer several advantages for self-powered photodetectors. They can be assembled into large area ordered structures such as ultra-thin layers, nanowire arrays, and quantum dot superlattices. Additionally, their atomic-level thickness provides a large specific surface area and facilitates integration with other materials. By combining different low-dimensional materials with complementary enhancements in bandgap, carrier transport rate, and light collection efficiency, the performance of self-powered photodetectors can be significantly improved. These devices can be scaled down to micro-nano levels while taking advantage of the adjustable bandgap, wide spectral response, high carrier migration rate, and high light absorption efficiency offered by low-dimensional materials. This article introduces the performance metrics of photodetectors, including photoresponsivity, noise equivalent power, detectivity, and response time. It then discusses the latest advancements in self-powered photodetectors based on 0D, 1D, and 2D materials. In the section on 0D material self-powered photodetectors, the device structure design using 0D materials as heterojunction components and doping materials is presented, highlighting their respective advantages. The section on 1D material self-powered photodetectors summarizes three main device structure types: planar, vertical, and core-shell, along with their individual advantages. The focus is placed on the content related to 2D material self-powered photodetectors. Graphene, transition metal dichalcogenides (TMDs), and black phosphorus are the most widely used 2D materials, and their preparation methods and the latest advancements in self-powered photodetectors are discussed. The controllable diversity in electrical properties resulting from interlayer interactions in two-dimensional materials offers great potential for new principles and multifunctional electronic devices. Finally, the article summarizes and discusses the key challenges and future development directions for self-powered photodetectors based on low-dimensional materials. In summary, the utilization of low-dimensional materials in self-powered photodetectors presents a promising direction for the development of advanced optoelectronic devices. By utilizing the unique properties of these materials, such as their atomic-level thickness, large specific surface area, and controllable electrical properties, significant advancements can be made in the field of self-powered photodetectors. The challenges associated with these materials, such as their complex fabrication processes, will need to be addressed to fully realize their potential in practical applications.