Hong Chengyun, Kim Hyundong, Tao Ye, Lim Jong Hyeon, Lee Jin Yong, Kim Ji-Hee
Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Department of Chemistry, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Sci Adv. 2025 Jan 3;11(1):eadr1534. doi: 10.1126/sciadv.adr1534. Epub 2025 Jan 1.
Metal electrode deposition is universally adopted in the community for optoelectronic device fabrication, inducing hybridization at electrode interfaces, and allows efficient extraction or injection of photocarriers. However, hybridization-induced midgap states increase photocarrier recombination pathways, creating a paradoxical trade-off. Here, we discovered that efficient photocarrier extraction and a long photocarrier lifetime can be achieved simultaneously in MoS/van der Waals Au contact, minimizing photocarrier loss at the interface. Using transient reflection spectroscopy, we quantified an ultrafast hole extraction time of 310 femtoseconds and a photocarrier lifetime of 259 picoseconds. Suppressed exciton formation in diffusion measurement validated ultrafast hole extraction. We further revealed a short photocarrier lifetime of ~8.7 picoseconds in deposited contact and negligible hole extraction in unintimate contact with space gap at the interface. We unraveled the hot electron transfer process from Au to MoS in different contact interfaces. Our results on different metal contact interfaces provide valuable insights into electrode engineering for future optoelectronic devices.
在光电器件制造领域，金属电极沉积被广泛采用，它会在电极界面引发杂化现象，并能实现光载流子的高效提取或注入。然而，杂化诱导的带隙中间态增加了光载流子的复合路径，从而形成了一种矛盾的权衡。在此，我们发现，在MoS/范德华金接触中能够同时实现高效的光载流子提取和较长的光载流子寿命，将界面处的光载流子损失降至最低。通过瞬态反射光谱，我们量化了310飞秒的超快空穴提取时间和259皮秒的光载流子寿命。扩散测量中激子形成的抑制证实了超快空穴提取。我们还发现，沉积接触中的光载流子寿命较短，约为8.7皮秒，而在界面处存在空间间隙的非紧密接触中，空穴提取可忽略不计。我们揭示了不同接触界面中从金到MoS的热电子转移过程。我们在不同金属接触界面上的研究结果为未来光电器件的电极工程提供了有价值的见解。
