Yonemoto Ryo, Ueda Rieko, Otomo Akira, Noguchi Yutaka
Graduate School of Science and Technology, Meiji University, Kawasaki 214-8571, Japan.
Advanced ICT Research Institute, National Institute of Information and Communications Technology, Kobe 651-2492, Japan.
Nano Lett. 2023 Aug 23;23(16):7493-7499. doi: 10.1021/acs.nanolett.3c02001. Epub 2023 Aug 14.
In a light-emitting electrochemical cell (LEC), electrochemical doping caused by mobile ions facilitates bipolar charge injection and recombination emissions for a high electroluminescence (EL) intensity at low driving voltages. We present the development of a nanogap LEC (i.e., nano-LEC) comprising a light-emitting polymer (F8BT) and an ionic liquid deposited on a gold nanogap electrode. The device demonstrated a high EL intensity at a wavelength of 540 nm corresponding to the emission peak of F8BT and a threshold voltage of ∼2 V at 300 K. Upon application of a constant voltage, the device demonstrated a gradual increase in current intensity followed by light emission. Notably, the delayed components of the current and EL were strongly suppressed at low temperatures (<285 K). The results clearly indicate that the device functions as an LEC and that the nano-LEC is a promising approach to realizing molecular-scale current-induced light sources.
在发光电化学电池（LEC）中，由移动离子引起的电化学掺杂有助于双极电荷注入和复合发光，从而在低驱动电压下实现高电致发光（EL）强度。我们展示了一种纳米间隙LEC（即纳米LEC）的开发，它由发光聚合物（F8BT）和沉积在金纳米间隙电极上的离子液体组成。该器件在540 nm波长处表现出高EL强度，对应于F8BT的发射峰，在300 K时阈值电压约为2 V。施加恒定电压后，该器件的电流强度逐渐增加，随后发光。值得注意的是，在低温（<285 K）下，电流和EL的延迟分量受到强烈抑制。结果清楚地表明该器件作为LEC发挥作用，并且纳米LEC是实现分子尺度电流感应光源的一种有前途的方法。
