Mixed dimensional Transition Metal Dichalcogenides (TMDs) vdW Heterostructure based Photodetectors: A review

Over the last two decades, low-dimensional nanomaterials such as zero-dimensional (0D), one-dimensional (1D), and two-dimensional (2D) have been used as functional materials in the development of photodetectors due to their extraordinary electronic and optical properties. However, developing broadband photodetectors with high responsivity with a single low-dimensional material is still an existing challenge. To overcome this, researchers have started exploring the mixed-dimensional van der Waals (vdW) heterostructures such as 0D-2D, 1D-2D and 2D-3D based photodetectors due to their wide absorption in the electromagnetic spectrum, low dark current, ultrahigh photoresponsivity, and fast response time. This review highlights the comprehensive compilation of transition-metal dichalcogenides (TMDs) based mixed-dimensional vdW heterostructure broadband photodetectors. First a brief insight into the fundamentals of photodetectors such types of photodetectors, photodetection mechanism, performance parameters, and type of band alignment is explained. Then the recent progress in various mixed-dimensional vdW heterostructures is summarized. Finally, challenges are discussed and directions for further development of mixed-dimensional broadband photodetectors are anticipated.