Shi Guozheng, Wang Haibin, Zhang Yaohong, Cheng Chen, Zhai Tianshu, Chen Botong, Liu Xinyi, Jono Ryota, Mao Xinnan, Liu Yang, Zhang Xuliang, Ling Xufeng, Zhang Yannan, Meng Xing, Chen Yifan, Duhm Steffen, Zhang Liang, Li Tao, Wang Lu, Xiong Shiyun, Sagawa Takashi, Kubo Takaya, Segawa Hiroshi, Shen Qing, Liu Zeke, Ma Wanli
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu, China.
Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo, Japan.
Nat Commun. 2021 Jul 19;12(1):4381. doi: 10.1038/s41467-021-24614-7.
Almost all surfaces sensitive to the ambient environment are covered by water, whereas the impacts of water on surface-dominated colloidal quantum dot (CQD) semiconductor electronics have rarely been explored. Here, strongly hydrogen-bonded water on hydroxylated lead sulfide (PbS) CQD is identified. The water could pilot the thermally induced evolution of surface chemical environment, which significantly influences the nanostructures, carrier dynamics, and trap behaviors in CQD solar cells. The aggravation of surface hydroxylation and water adsorption triggers epitaxial CQD fusion during device fabrication under humid ambient, giving rise to the inter-band traps and deficiency in solar cells. To address this problem, meniscus-guided-coating technique is introduced to achieve dense-packed CQD solids and extrude ambient water, improving device performance and thermal stability. Our works not only elucidate the water involved PbS CQD surface chemistry, but may also achieve a comprehensive understanding of the impact of ambient water on CQD based electronics.
几乎所有对周围环境敏感的表面都被水覆盖，而水对以表面为主的胶体量子点（CQD）半导体电子器件的影响却鲜有研究。在此，我们识别出了羟基化硫化铅（PbS）CQD上存在强氢键结合的水。这种水能够引导表面化学环境的热致演化，这对CQD太阳能电池中的纳米结构、载流子动力学和陷阱行为有显著影响。表面羟基化和水吸附的加剧会在潮湿环境下的器件制造过程中引发外延CQD融合，导致太阳能电池中出现带间陷阱和缺陷。为解决这一问题，引入了弯月面引导涂层技术来实现紧密堆积的CQD固体并挤出环境中的水，从而提高器件性能和热稳定性。我们的工作不仅阐明了水参与的PbS CQD表面化学，还可能实现对环境水对基于CQD的电子器件影响的全面理解。
