Mixed-dimensional van der Waals heterojunctions have attracted a great deal of attention due to their excellent photoelectric conversion capability, which have been widely applied for self-powered photoelectrochemical (PEC)-type devices as the growing demands of clean energy, environmental governance and protection, and the underwater communications. In this work, 0D Bismuth quantum dots (Bi QDs) encapsulated 2D g-C₃N₄ nanosheets (g-C₃N₄@Bi) mixed-dimensional heterojunctions were prepared and spined on ITO-coated polyethylene terephthalate (PET) substrate for working as self-powered PEC-type photodetector (PD). Density functional theory calculations evidenced the successful construction of a type II van der Waals heterojunction between g-C₃N₄ and Bi as well as its enhanced optoelectronic characteristics. Benefiting from the superior properties of g-C₃N₄@Bi, the as-prepared PD exhibits a high photocurrent of 5.02 μA cm^-2, a responsivity of 2843.14 μA W^-1, and a specific detectivity of 2.25× 10¹¹ Jones at 0 V. Furthermore, the PD exhibits self-powered capability after 1,000 cycles of bending, and the stable and repeatable ON/OFF signals can be detected over 90 days, indicating the excellent long-term stability and the potential of g-C₃N₄@Bi-based PD in practical applications.

混合尺寸范德华异质结由于其出色的光电转换能力而备受关注，随着清洁能源，环境治理和保护的不断增长的需求，其已广泛应用于自供电光电化学（PEC）型器件，以及水下通讯。在这项工作中，0D铋量子点（Bi QDs）封装了2D gC ₃ N ₄纳米片（gC ₃ N ₄制备（Bi）混合尺寸的异质结，并旋涂在ITO涂层的聚对苯二甲酸乙二醇酯（PET）衬底上，以用作自供电的PEC型光电探测器（PD）。密度泛函理论计算证明了gC ₃ N ₄和Bi之间II型范德华异质结的成功构建及其增强的光电特性。得益于gC ₃ N ₄ @Bi的优异性能，如此制备的PD表现出5.02μAcm ^-2的高光电流，2843.14μAW ^-1的响应度和2.25×10 ¹¹的比检测率。Jones在0 V电压下工作。此外，PD在经过1000次弯曲循环后表现出自供电能力，并且可以在90天之内检测到稳定且可重复的ON / OFF信号，这表明出色的长期稳定性和gC ₃ N的潜力₄实际应用中基于@Bi的PD。