Harvesting infrared (IR) sunlight using colloidal quantum dots (CQDs) holds significant promise for optoelectronic devices including photovoltaics (PVs) and self‐powered sensors. Traditionally, Pb chalcogenides have been utilized in energy devices, but needs for RoHS compliance derive the development of Pb‐free alternatives. A key challenge with Pb‐free materials is the low photovoltage in devices, primarily due to recombination in surface defects and interfaces within the architectures. Here, the Pb‐free CQD PVs capable of harvesting the IR light beyond the Si PVs are first presented. Designing an InAs CQD‐based homojunction architecture, with n‐type InAs absorbers passivated with multifunctional ligands and p‐type conductive InAs inks, efficient charge extraction is achieved while suppressing interface recombination. Additionally, the IR light path is modulated to match the absorber's absorption to optimize the performance. This led to InAs PVs with absorber bandgaps ranging from 1.35 to 1.03 eV, significantly improving the open‐circuit voltage from 0.05 to 0.26 V and fill factor from 29% to 50%, comparable to Pb‐based PVs. The InAs IR‐PVs exhibit a power conversion efficiency of 2.00% under one‐sun and 0.27% with a Si filter, outperforming control ones (0.28% and 0.03%). This work provides an effective strategy for designing Pb‐free, energy‐independent IR optoelectronics.

中文翻译：

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使用 n-p 同质结结构的无铅红外收集胶体量子点太阳能电池


使用胶体量子点 （CQD） 收集红外 （IR） 太阳光，为光伏 （PV） 和自供电传感器等光电设备带来了重大前景。传统上，Pb 硫属化物已用于能源设备，但符合 RoHS 的要求催生了无铅替代品的开发。无铅材料的一个关键挑战是器件中的低光电压，这主要是由于结构内的表面缺陷和界面的复合。在这里，首先介绍了能够收集 Si PV 之外的红外光的无铅 CQD PV。设计基于 InAs CQD 的同结架构，使用多功能配体钝化的 n 型 InAs 吸收剂和 p 型导电 InAs 油墨，在抑制界面复合的同时实现高效的电荷提取。此外，红外光路经过调制以匹配吸收体的吸收，以优化性能。这导致 InAs PV 的吸收带隙范围为 1.35 至 1.03 eV，将开路电压从 0.05 V 显著提高到 0.26 V，填充因子从 29% 提高到 50%，与铂基 PV 相当。InAs IR-PV 在单太阳下表现出 2.00% 的功率转换效率，在硅滤光片下表现出 0.27% 的功率转换效率，优于对照产品（0.28% 和 0.03%）。这项工作为设计无铅、能量无关的红外光电子学提供了一种有效的策略。