Fu Shuai, Huang Xing, Gao Guoquan, St Petkov Petko, Gao Wenpei, Zhang Jianjun, Gao Lei, Zhang Heng, Liu Min, Hambsch Mike, Zhang Wenjie, Zhang Jiaxu, Li Keming, Kaiser Ute, Parkin Stuart S P, Mannsfeld Stefan C B, Zhu Tong, Wang Hai I, Wang Zhiyong, Dong Renhao, Feng Xinliang, Bonn Mischa
Center for Advancing Electronics Dresden and Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Dresden, Germany.
Max Planck Institute for Polymer Research, Mainz, Germany.
Nat Mater. 2025 May 13. doi: 10.1038/s41563-025-02246-2.
Hot carriers, inheriting excess kinetic energy from high-energy photons, drive numerous optoelectronic applications reliant on non-equilibrium transport processes. Although extensively studied in inorganic materials, their potential in organic-based systems remains largely unexplored. Here we demonstrate highly mobile hot carriers in crystalline two-dimensional conjugated coordination polymer CuBHT (BHT, benzenehexathiol) films. Leveraging a suite of ultrafast spectroscopic and imaging techniques, we map the microscopic charge transport landscape in CuBHT films following non-equilibrium photoexcitation across temporal, spatial and frequency domains, revealing two distinct high-mobility transport regimes. In the non-equilibrium regime, hot carriers achieve an ultrahigh mobility of ~2,000 cm V s, traversing grain boundaries up to ~300 nm within a picosecond. In the quasi-equilibrium regime, free carriers exhibit Drude-type, band-like transport with a remarkable mobility of ~400 cm V s and an intrinsic diffusion length exceeding 1 μm. These findings position two-dimensional conjugated coordination polymers as versatile platforms for advancing organic-based hot carrier applications.
热载流子从高能光子中继承了过量的动能，驱动了众多依赖非平衡输运过程的光电子应用。尽管在无机材料中已得到广泛研究，但其在有机基体系中的潜力仍 largely 未被探索。在此，我们展示了结晶二维共轭配位聚合物 CuBHT（BHT，苯六硫醇）薄膜中具有高迁移率的热载流子。利用一系列超快光谱和成像技术，我们在非平衡光激发后，跨越时间、空间和频率域绘制了 CuBHT 薄膜中的微观电荷输运图景，揭示了两种不同的高迁移率输运机制。在非平衡机制中，热载流子实现了约 2000 cm V s 的超高迁移率，在皮秒内穿越高达约 300 nm 的晶界。在准平衡机制中，自由载流子表现出德鲁德型的带状输运，具有约 400 cm V s 的显著迁移率和超过 1 μm 的本征扩散长度。这些发现将二维共轭配位聚合物定位为推进有机基热载流子应用的通用平台。
