摘要
To further improve the quantum efficiency of atomically thin transition metal dichalcogenides (TMDs) is crucial for the realization of high-performance optoelectronic applications. To this regard, a few chemical or physical approaches such as superacid treatment, electrical gating, dielectric screening, and laser irradiation have been developed. In particular, the laser irradiation appears to be a more efficient way with good processability and spatial selectivity. However, the underlying mechanism especially about whether chemisorption or physisorption plays a more important role is still debatable. Here, we unravel the mystery of laser irradiation induced photoluminescence enhancement in monolayer WS_(2) by precisely controlling irradiation time and environment. It is found that the synergetic effect of physisorption and chemisorption is responsible for the photoluminescence enhancement, where the physisorption dominates with more than 74% contribution. The comprehensive understanding of the adsorption mechanism in laser-irradiated TMDs may trigger the potential applications for patterned light source, effective photosensor and ultrathin optical memory.
基金
Y. Li and J. Yan contributed equally to this work. This work was supported by the Program of National Natural Science Foundation of China (Nos. 51732003, 51872043, 61604037, 11874104, 12074060, and 12004069)
the National Science Fund for Distinguished Young Scholars (No. 52025022)
the “111” Project (No. B13013)
the National Key Research and Development Program of China (Nos. 2016YFA0201902 and 2019YFB2205100)
Fund from Ministry of Education (No. 6141A02033414)
Shenzhen Nanshan District Pilotage Team Program (No. LHTD20170006)
the China Postdoctoral Science Foundation funded project (Nos. 2020M681025, 2021T140109, and 2021M693905)
the Fundamental Research Funds for the Central Universities (Nos. 2412020QD015, 2412019BJ006, 2412021ZD007, 2412021ZD012, and 2412019FZ034)
Postdoctoral Science Foundation funded project from Jilin Province (No. 111865005)
the Fund from Jilin Province (Nos. YDZJ202101ZYTS049, YDZJ202101ZYTS041, YDZJ202101ZYTS133, JJKH20211273KJ, JJKH20211274KJ, and 20190103007JH).
