Abstract：
Short-wave infrared (SWIR) light-emitting diodes (LEDs) have emerged as promising technologies for diverse applications such as optical communication, biomedical imaging, surveillance, and machine vision. Colloidal quantum dots (QDs) are particularly attractive for SWIR LEDs due to their solution processability, compatibility with flexible substrates, and tunable absorption and luminescence. However, the presence of toxic elements or precious metals in most SWIR-emitting QDs poses health, environmental, and cost challenges. In this context, CuInS2 (CIS) QDs are known for low toxicity, cost-effective fabrication, and SWIR-light emitting capability. However, CIS QDs have not yet been directly utilized to fabricate SWIR LEDs to date, which is due to low particle stability, inefficient charge carrier recombination, and significantly blue-shifted luminescence after integrating into LED devices. To address challenges, we propose a dual-passivation strategy using ZnI2 as a chemical additive to enhance both the optical property of plain CIS QDs and charge carrier recombination upon LED device implementation. The resulting CIS-QD-based LEDs exhibit a stable SWIR electroluminescence (EL) peak (over 1000 nm) with a high EL radiance and a record external quantum efficiency in the SWIR region. Our study represents a significant step forward in SWIR-QLED technology, offering a pathway for the development of high-performance, low-cost, and nontoxic SWIR light sources.
摘要：
短波红外（SWIR）发光二极管（LED）已成为光通信等多种应用的有前途的技术，生物医学成像，监视,和机器视觉。胶体量子点（QD）由于其溶液可加工性而对SWIRLED特别有吸引力，与柔性基板的兼容性，和可调吸收和发光。然而,大多数SWIR发射量子点中有毒元素或贵金属的存在会带来健康，环境,和成本挑战。在这种情况下，CuInS2(CIS)量子点是众所周知的低毒性，具有成本效益的制造，和SWIR发光能力。然而,迄今为止，CISQD尚未直接用于制造SWIRLED，这是由于粒子稳定性低，低效的电荷载流子复合，以及集成到LED器件后的显着蓝移发光。为了应对挑战，我们提出了一种使用ZnI2作为化学添加剂的双钝化策略，以增强纯CISQD的光学性能和在LED器件实现时的电荷载流子复合。所得的基于CIS-QD的LED表现出稳定的SWIR电致发光（EL）峰（超过1000nm），具有高EL辐射度，并且在SWIR区域具有记录的外部量子效率。我们的研究代表了SWIR-QLED技术向前迈出的重要一步，为高性能的发展提供了一条途径，低成本,和无毒的SWIR光源。
