北京大学周航团队近日研究了用于低剂量近红外光探测和图像通信的高响应度胶体量子点光电晶体管。2025年5月19日出版的《光：科学与应用》杂志发表了这项成果。

成像、移动、医疗保健、汽车和光通信等领域对红外光电探测器（IRPD）的需求和采用激增，但传统IRPD材料（如InGaAs和HgCdTe）的高昂成本阻碍了IRPD的发展。量子点（QD），特别是铅硫族化物（PbS）QD，由于其高光吸收系数、可调带隙、低制造成本和器件兼容性，代表了用于近红外（NIR）检测的下一代低带隙半导体。已经提出了配体交换过程等创新技术来提高PbS量子点光电探测器的性能，主要使用1,2-乙二硫醇（EDT）和碘化四丁基铵（TBAI）等短配体。 

研究组探索了使用长链二硫醇配体来提高PbS QDs/InGaZnO光电晶体管的响应率。发现长链二硫醇配体可以抑制水平电子传输/泄漏和电子捕获，这有利于响应性。利用1,10-癸二硫醇（DDT）的新型配体交换技术，他们开发了检测率超过1014-Jones的高性能混合光电晶体管。

基于这些光电晶体管，研究组通过近红外光通信系统演示了图像通信。长配体PbS-QDs/InGaZnO混合光电晶体管在近红外低剂量成像和光通信方面显示出巨大的潜力，特别是在需要检测低频弱光信号的情况下。

附：英文原文

Title: High responsivity colloidal quantum dots phototransistors for low-dose near-infrared photodetection and image communication

Author: Zhan, Shijie, Li, Benxuan, Chen, Tong, Tu, Yudi, Ji, Hong, Othman, Diyar Mousa, Xiao, Mingfei, Liu, Renjun, Zhang, Zuhong, Tang, Ying, Ming, Wenlong, Li, Meng, Zhou, Hang, Hou, Bo

Issue&Volume: 2025-05-19

Abstract: The surging demand and adoption of infrared photodetectors (IRPDs) in sectors of imaging, mobile, healthcare, automobiles, and optical communication are hindered by the prohibitive costs of traditional IRPD materials such as InGaAs and HgCdTe. Quantum dots (QDs), especially lead chalcogenide (PbS) QDs, represent the next-generation low-bandgap semiconductors for near-infrared (NIR) detection due to their high optical absorption coefficient, tunable bandgap, low fabrication costs, and device compatibility. Innovative techniques such as ligand exchange processes have been proposed to boost the performance of PbS QDs photodetectors, mostly using short ligands like 1,2-ethanedithiol (EDT) and tetrabutylammonium iodide (TBAI). Our study explores the use of long-chain dithiol ligands to enhance the responsivity of PbS QDs/InGaZnO phototransistors. Long-chain dithiol ligands are found to suppress horizontal electron transport/leakage and electron trapping, which is beneficial for responsivity. Utilizing a novel ligand-exchange technique with 1,10-decanedithiol (DDT), we develop high-performance hybrid phototransistors with detectivity exceeding 1014 Jones. Based on these phototransistors, we demonstrate image communication through a NIR optical communication system. The long-ligand PbS QDs/InGaZnO hybrid phototransistor demonstrates significant potential for NIR low-dose imaging and optical communication, particularly in scenarios requiring the detection of weak light signals at low frequencies.

DOI: 10.1038/s41377-025-01853-7

Source: https://www.nature.com/articles/s41377-025-01853-7