Recent progress in photodetectors based on low-dimensional nanomaterials

Photodetectors (PDs) have great potential in applications of imaging, telecommunication, and biological sensing. In this article, state-of-the-art achievements on typical low-dimensional nanostructured PDs and hybrid PDs are reviewed. In the 2D nanostructured PDs part, 2D transition metal dichalcogenides have a natural gap, which promise high sensitivity of photodetection. Graphene and black phosphorus can also stand for 2D nanostructured PDs due to their broadband absorption and tunable direct bandgap, respectively. In the 1D nanostructured PDs part, owing to its high photoconductive characteristic, ZnO nanowire film is a promising material for ultraviolet PDs. Carbon nanotubes show potential in infrared (IR) detection due to its unique physical properties. In the 0D nanostructured PDs part, lead sulfide has a small bandgap and large Bohr exciton radius, which collectively give it a wide spectral tunability in the IR. In the hybrid PDs part, electrical and chemical doping is applied to combine different nanomaterials to realize PDs with high performance. In each part, the present situation and major challenges are overviewed. Then, the evolutions of the methods to overcome these challenges and the tremendous research breakthroughs are demonstrated. At last, future directions that could improve the performance of PDs are discussed.