基于硫蒸气处理转移的单层二硫化钼的荧光增强

Enhanced Photoluminescence of Transferred Monolayer MoS2 via Sulfur Vapor Treatment

采用化学气相沉积法在SiO2/Si衬底上制备了单层MoS2,再通过300℃硫蒸气处理用聚甲基丙烯酸甲酯(Polymethyl Methacrylate,PMMA)转移下的单层MoS2.使用原子力显微镜、真空荧光检测和拉曼光谱等手段表征了样品的形貌和光致发光性能.结果表明:经过硫蒸气处理转移后的单层MoS2的光致发光强度比由化学气相沉积法制备的未处理的单层MoS2的光致发光强度增强了约5倍.光致发光强度增强是由于在硫蒸气处理过程中,单层MoS2的部分硫空位被硫原子纳米团簇所填补,从而提高了光致发光效率.此外,分别将单层MoS2转移到SiO2/Si衬底、石英、三氧化铝及氟化镁衬底再经过硫处理后,也观察到了类似的荧光增强现象.

Monolayer molybdenum disulfide(MoS2)was prepared on the SiO2/Si substrate by Chemical Vapor Deposition(CVD)method,and then treated with sulfur vapor at 300℃after the monolayer MoS2 transferred to desired substrate by polymethyl methacrylate.The morphology and photoluminescence properties of the samples were characterized by Atomic Force Microscopy(AFM),vacuum fluorescence detection and Raman spectroscopy.The results show that the photoluminescence intensity of the transferred monolayer MoS2 after sulfur vapor treatment is about 5 times higher than that of the untreated monolayer MoS2 prepared by CVD.This photoluminescence enhancement effect is due to that part of the sulfur vacancies of the monolayer MoS2 are filled by the sulfur atom nanoclusters during the sulfur vapor treatment,thereby improving the photoluminescence efficiency.In addition,similar photoluminescence enhancement is observed after sulfur treatment were observed in the monolayer MoS2 transferred to SiO2/Si substrate,quartz,alumina,and magnesium fluoride substrates,respectively.