Vacuum-Ultraviolet-Oriented van der Waals Photovoltaics

Unlike traditional three-dimensional semiconductors, when van der Waals semiconductors are integrated to other materials, “lattice mismatch” in the vertical direction can be avoided because there is no dangling bond on their plane surfaces. Here, taking full advantage of the benefit of van der Waals heterostructure, we constructed the first vacuum-ultraviolet photovoltaic device of graphene/hexagonal boron nitride (h-BN)/silicon carbide (SiC), which shows ultrahigh performance on VUV photodetection and is expected to meet the requirements for space exploration. The device is the van der Waals photovoltaic device with the shortest response cutoff wavelength (which is located at 227 nm) reported so far. At 0 V bias, the device exhibits an ultrafast response time of 680 ns, which is 2–3 orders of magnitude faster than that of photoconductive h-BN photodetectors. Our work breaks new ground for the application of van der Waals materials and devices and opens up a potential application scenario in the future, in which space exploration is dependent on VUV photodetection.