Tebyetekerwa Mike, Cheng Yanhua, Zhang Jian, Li Weili, Li Hongkun, Neupane Guru Prakash, Wang Bowen, Truong Thien N, Xiao Chuanxiao, Al-Jassim Mowafak M, Yin Zongyou, Lu Yuerui, Macdonald Daniel, Nguyen Hieu T
Research School of Electrical, Energy and Materials Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, ACT 2601, Australia.
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P.R. China.
ACS Nano. 2020 Jun 23;14(6):7444-7453. doi: 10.1021/acsnano.0c03086. Epub 2020 May 18.
Organic-inorganic (O-I) heterostructures, consisting of atomically thin inorganic semiconductors and organic molecules, present synergistic and enhanced optoelectronic properties with a high tunability. Here, we develop a class of air-stable vertical O-I heterostructures comprising a monolayer of transition-metal dichalcogenides (TMDs), including WS, WSe, and MoSe, on top of tetraphenylethylene (TPE) core-based aggregation-induced emission (AIE) molecular rotors. The created O-I heterostructures yields a photoluminescence (PL) enhancement of up to ∼950%, ∼500%, and ∼330% in the top monolayer WS, MoSe, and WSe as compared to PL in their pristine monolayers, respectively. The strong PL enhancement is mainly attributed to the efficient photogenerated carrier process in the AIE luminogens (courtesy of their restricted intermolecular motions in the solid state) and the charge-transfer process in the created type I O-I heterostructures. Moreover, we observe an improvement in photovoltaic properties of the TMDs in the heterostructures including the quasi-Fermi level splitting, minority carrier lifetime, and light absorption. This work presents an inspiring example of combining stable, highly luminescent AIE-based molecules, with rich photochemistry and versatile applications, with atomically thin inorganic semiconductors for multifunctional and efficient optoelectronic devices.
有机-无机（O-I）异质结构由原子级薄的无机半导体和有机分子组成，具有协同增强的光电特性且可调性高。在此，我们开发了一类空气稳定的垂直O-I异质结构，其由基于四苯基乙烯（TPE）核的聚集诱导发光（AIE）分子转子顶部的单层过渡金属二硫属化物（TMD）组成，包括WS、WSe和MoSe。与原始单层相比，所制备的O-I异质结构在顶部单层WS、MoSe和WSe中分别产生高达约950%、约500%和约330%的光致发光（PL）增强。强烈的PL增强主要归因于AIE发光体中高效的光生载流子过程（得益于其在固态下受限的分子间运动）以及所形成的I型O-I异质结构中的电荷转移过程。此外，我们观察到异质结构中TMD的光伏特性有所改善，包括准费米能级分裂、少数载流子寿命和光吸收。这项工作展示了一个鼓舞人心的例子，即将具有丰富光化学和广泛应用的稳定、高发光的基于AIE的分子与原子级薄的无机半导体相结合，用于多功能高效光电器件。
