Kim Changjo, Kozakci Irem, Lee Sang Yeon, Kim Byeongsu, Kim Junho, Lee Jihyung, Ma Boo Soo, Oh Eun Sung, Kim Taek-Soo, Lee Jung-Yong
School of Electrical Engineering (EE), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
Information and Electronics Research Institute, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
Small. 2023 Oct;19(41):e2302195. doi: 10.1002/smll.202302195. Epub 2023 Jun 10.
Lead sulfide (PbS) colloidal quantum dots (CQDs) are promising materials for next-generation flexible solar cells because of near-infrared absorption, facile bandgap tunability, and superior air stability. However, CQD devices still lack enough flexibility to be applied to wearable devices owing to the poor mechanical properties of CQD films. In this study, a facile approach is proposed to improve the mechanical stability of CQDs solar cells without compromising the high power conversion efficiency (PCE) of the devices. (3-aminopropyl)triethoxysilane (APTS) is introduced on CQD films to strengthen the dot-to-dot bonding via QD-siloxane anchoring, and as a result, crack pattern analysis reveals that the treated devices become robust to mechanical stress. The device maintains 88% of the initial PCE under 12 000 cycles at a bending radius of 8.3 mm. In addition, APTS forms a dipole layer on CQD films, which improves the open circuit voltage (V ) of the device, achieving a PCE of 11.04%, one of the highest PCEs in flexible PbS CQD solar cells.
硫化铅（PbS）胶体量子点（CQD）由于具有近红外吸收、易于调节带隙以及出色的空气稳定性，是下一代柔性太阳能电池的理想材料。然而，由于CQD薄膜的机械性能较差，CQD器件仍缺乏足够的柔韧性以应用于可穿戴设备。在本研究中，我们提出了一种简便的方法来提高CQD太阳能电池的机械稳定性，同时不影响器件的高功率转换效率（PCE）。通过（3-氨丙基）三乙氧基硅烷（APTS）对CQD薄膜进行处理，通过量子点-硅氧烷锚固增强点与点之间的键合，裂纹模式分析表明，经过处理的器件对机械应力具有更强的抗性。该器件在弯曲半径为8.3毫米的情况下，经过12000次循环后仍保持初始PCE的88%。此外，APTS在CQD薄膜上形成偶极层，提高了器件的开路电压（V），实现了11.04%的PCE，这是柔性PbS CQD太阳能电池中最高的PCE之一。
