Photogalvanic effect (PGE) enables a self-powered and highly polarization-sensitive ultraviolet photodetection (UV-PHD), however the photocurrent generated in the PGE is usually small, leading to a lower photoresponsivity. Here, using quantum transport simulations, we propose a self-powered UV photodetector composed of the two-dimensional lateral ZrNBr-ZrNCl heterojunction. Robust PGE photocurrent is generated in a broad UV range from 3.5 to 6.5 eV at zero bias due to the noncentrosymmetry of the photodetector. The photocurrent is enhanced by up to 3 orders of magnitude, as compared to that in the monolayer ZrNBr and ZrNCl, and moreover, a good polarization sensitivity is obtained with an extinction ratio of up to 5.0. Our result propose that the PGE photocurrent can be effectively enhanced by an appropriate lateral heterojunction, and shows a promising application of the lateral ZrNBr-ZrNCl heterojunction in the self-powered and polarization-sensitive UV-PHD.

光电效应（PGE）可以实现自供电且高度偏振敏感的紫外线光电检测（UV-PHD），但是PGE中产生的光电流通常很小，从而导致较低的光响应性。在这里，我们使用量子传输模拟，提出了一种由二维横向ZrNBr-ZrNCl异质结组成的自供电紫外光电探测器。由于光电检测器的非中心对称性，在零偏压下在3.5至6.5 eV的宽UV范围内会产生强大的PGE光电流。与单层ZrNBr和ZrNCl相比，光电流提高了3个数量级，此外，消光比高达5.0，获得了良好的偏振灵敏度。我们的结果表明，适当的横向异质结可以有效地增强PGE的光电流，