Wang Chih-Wei, Kim Hong Rae, Hampton Jared, Kim Doyun, Tu Qing, Pyun Jae-Chul, Son Dong Hee
Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA.
Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-Ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
J Chem Phys. 2023 Aug 7;159(5). doi: 10.1063/5.0156528.
In this work, we investigated the effect of hole transporting poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) interfacing with Mn-doped CdS/ZnS quantum dots (QDs) deposited on an indium tin oxide (ITO) substrate on the photoemission of upconverted hot electrons under weak continuous wave photoexcitation in a vacuum. Among the various factors that can influence the photoemission of the upconverted hot electrons, we studied the role of PEDOT:PSS in facilitating the hole transfer from QDs and altering the energy of photoemitted hot electrons. Compared to hot electrons emitted from QDs deposited directly on the ITO substrate, the addition of the PEDOT:PSS layer between the QD and ITO layers increased the energy of the photoemitted hot electrons. The increased energy of the photoemitted hot electrons is attributed in part to the reduced steady-state positive charge on the QDs under continuous photoexcitation, which reduces the energy required to eject the electron from the conduction band.
在这项工作中，我们研究了在真空中弱连续波光激发下，与沉积在氧化铟锡（ITO）衬底上的锰掺杂硫化镉/硫化锌量子点（QDs）相接触的空穴传输聚合物聚（3,4-乙撑二氧噻吩）：聚苯乙烯磺酸盐（PEDOT:PSS）对向上转换热电子光发射的影响。在各种能够影响向上转换热电子光发射的因素中，我们研究了PEDOT:PSS在促进空穴从量子点转移以及改变光发射热电子能量方面的作用。与直接沉积在ITO衬底上的量子点发射的热电子相比，在量子点层和ITO层之间添加PEDOT:PSS层提高了光发射热电子的能量。光发射热电子能量的增加部分归因于连续光激发下量子点上稳态正电荷的减少，这降低了从导带中射出电子所需的能量。
