Kim Jun Suk, Tran Minh Dao, Kim Sung Tae, Yoo Daehan, Oh Sang-Hyun, Kim Ji-Hee, Lee Young Hee
Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS), Suwon 16419, Republic of Korea.
Department of Energy Science, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea.
Nano Lett. 2021 Mar 10;21(5):1976-1981. doi: 10.1021/acs.nanolett.0c04410. Epub 2021 Feb 16.
Although van der Waals-layered transition metal dichalcogenides from transient absorption spectroscopy have successfully demonstrated an ideal carrier multiplication (CM) performance with an onset of nearly 2E, interpretation of the CM effect from the optical approach remains unresolved owing to the complexity of many-body electron-hole pairs. We demonstrate the escalated photocurrent with excitation photon energy by fabricating the dual-gate p-n junction of a MoTe film on a transparent substrate. Electrons and holes were efficiently extracted by eliminating the Schottky barriers in the metal contact and minimizing multiple reflections. The photocurrent was elevated proportionately to the excitation photon energy. The boosted quantum efficiency confirms the multiple electron-hole pair generation of >2E, consistent with CM results from an optical approach, pushing the solar cell efficiency beyond the Shockley-Queisser limit.
尽管通过瞬态吸收光谱法研究的范德华层状过渡金属二硫属化物已成功展示出理想的载流子倍增(CM)性能,其起始能量接近2E,但由于多体电子-空穴对的复杂性,从光学方法对CM效应的解释仍未解决。我们通过在透明衬底上制备MoTe薄膜的双栅p-n结,展示了随着激发光子能量增加的光电流。通过消除金属接触中的肖特基势垒并最小化多次反射,电子和空穴得以有效提取。光电流与激发光子能量成比例增加。提高的量子效率证实了产生了大于2E的多电子-空穴对,这与光学方法得到的CM结果一致,推动太阳能电池效率超越了肖克利-奎塞尔极限。