Xu Wen, Qin Shuchao, Du Qianqian, Zhang Yongji, Zhang Yanxun, Wang Wenjun, Wang Fengqiu
School of Physical Science and Information Engineering, Liaocheng University, Liaocheng, 252059, China.
National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.
Adv Sci (Weinh). 2025 Aug 13:e08332. doi: 10.1002/advs.202508332.
Organic semiconductors have demonstrated exceptional performance due to their inherent advantages such as simple processability, and superior mechanical properties. Developing polarization-sensitive near-infrared (NIR) organic photodetectors is crucial for their application in target recognition, biological imaging, and wearable optoelectronics. However, high-performance NIR photon detection still faces challenges for organic materials, due to their intrinsic limitations including low carrier mobility, and poor exciton dissociation. Here, a polarization-sensitive NIR photodetector is demonstrated with a linear dichroic ratio of 5.3, employing a two-dimensional (2D) TiOPc single-crystal/graphene heterostructure. Remarkable absorption, optimized exciton diffusion of single crystal, and efficient interfacial charge transfer enable a high NIR responsivity of > 10 A W and specific detectivity of 10 Jones for 980 nm irradiation, with a reasonable -3 dB bandwidth of >1 kHz. Under 850 nm illumination, it exhibits an even higher responsivity of > 10 A W and specific detectivity of > 10 Jones, attributed to stronger absorption. This NIR responsivity represents a tenfold improvement over existing organic polarization photodetectors. Finally, the high-resolution polarization-dependent single-pixel imaging in NIR range is achieved, highlighting its great potential for image recognition applications. This work opens new avenues for exploiting high-performance NIR polarized photodetectors.
有机半导体因其固有的优势，如简单的可加工性和优异的机械性能，已展现出卓越的性能。开发偏振敏感型近红外（NIR）有机光电探测器对于其在目标识别、生物成像和可穿戴光电子学中的应用至关重要。然而，由于有机材料存在本征局限性，包括低载流子迁移率和较差的激子解离，高性能近红外光子探测仍面临挑战。在此，通过采用二维（2D）TiOPc单晶/石墨烯异质结构，展示了一种线性二向色比为5.3的偏振敏感型近红外光电探测器。显著的吸收、单晶中优化的激子扩散以及高效的界面电荷转移，使得在980nm光照下具有大于10 A/W的高近红外响应度和10 Jones的比探测率，同时具有大于1kHz的合理-3dB带宽。在850nm光照下，由于更强的吸收，其表现出更高的响应度，大于10 A/W，比探测率大于10 Jones。这种近红外响应度相较于现有的有机偏振光电探测器提高了十倍。最后，实现了近红外范围内的高分辨率偏振依赖单像素成像，突出了其在图像识别应用中的巨大潜力。这项工作为开发高性能近红外偏振光电探测器开辟了新途径。
