In spite of the great promise they hold for a broad range of applications, two- dimensional (2D) transition metal dichalcogenides (TMDCs) have had a significant drawback of poor photoluminescence (PL) quantum yield (QY) at room temperature. Among a number of studies which have suggested the way to improve QY, superacid treatment, one of the most promising strategies, has enhanced the QY of TMDCs to near 100%. However, insufficient treatment yield and instability of enhanced QY have emerged as critical obstacles to this approach towards practical applications in real devices. In this work, we demonstrate the 2D TMDCs with near-perfect optoelectronic properties and high stability against the external environment. By a simple method which consists of superacid treatment and the encapsulation of 2D TMDCs with an amorphous fluoropolymer, our proposed work not only preserves the QY enhancement but also substantially improves the yield of treatment, leading to the uniformly improved QY near 100% at low injection levels. Since we also demonstrate that our encapsulating layer followed by superacid treatment can be patterned by general photolithography and compatible with subsequent fabrication process, our work presents a novel route of being directly applicable for a new class of optoelectronic devices.
Project end date: 08/11/18