In-Plane Bulk Photovoltaic Effect in a MoSe 2 /NbOI 2 Heterojunction for Efficient Polarization-Sensitive Self-Powered Photodetection

作者：Xiong Huang, Qi Wang, Kejian Song, Qichuan Hu, Huaihao Zhang, Xingsen Gao, Mingzhu Long, Jinyou Xu, Zuxin Chen, Guofu Zhou, Bo Wu · 发表于：Nano Letters · 年份：2025 · DOI：10.1021/acs.nanolett.4c05418 · 被引用次数：23 · 研究领域：2D Materials and Applications、Multiferroics and related materials、Perovskite Materials and Applications

Two-dimensional ferroelectric materials can generate a bulk photovoltaic effect, making them highly promising for self-powered photodetectors. However, their practical application is limited by a weak photoresponse due to a weak transition strength and wide band gap. In this study, we construct a van der Waals heterojunction using NbOI 2, which has significant in-plane polarization, with a highly absorbing MoSe 2 layer. We observe ultrafast hole transfer from MoSe 2 to NbOI 2 within 0.4 ps and electron transfer in the opposite direction within 3.8 ps, facilitating efficient charge dissociation and extraction. Applying a direct current electric field poling modulates the ferroelectric domains in NbOI 2, enhancing the bulk photovoltaic effect. This results in one of the highest responsivities for self-powered photodetectors (101.3 mA/W) at 0 V bias alongside excellent polarization sensitivity (∼7.58). This work advances the understanding of self-powering mechanisms via the bulk photovoltaic effect and proposes new strategies for future self-powered devices.