title: Novel Excitonic Solar Cells in Phosphorene-TiO2 Heterostructures with Extraordinary Charge Separation Efficiency.
abstract: Constructing van der Waals heterostructures is an efficient approach to modulate the electronic structure, to advance the charge separation efficiency, and thus to optimize the optoelectronic property. Here, we theoretically investigated the phosphorene interfaced with TiO2(110) surface (1L-BP/TiO2) with a type-II band alignment, showing enhanced photoactivity. The 1L-BP/TiO2 excitonic solar cell (XSC) based on the 1L-BP/TiO2 exhibits large built-in potential and high power conversion efficiency (PCE), dozens of times higher than conventional solar cells, comparable to MoS2/WS2 XSC. The nonadiabatic molecular dynamics simulation shows the ultrafast electron transfer time of 6.1 fs, and slow electron-hole recombination of 0.58 ps, yielding >98% internal quantum efficiency for charge separation, further guaranteeing the practical PCE. Moreover, doping in phosphorene has a tunability on built-in potential, charge transfer, light absorbance, as well as electron dynamics, which greatly helps to optimize the optoelectronic efficiency of a XSC.
authors.affiliation: Bremen Center for Computational Materials Science, University of Bremen , Am Falturm 1, 28359 Bremen, Germany.
authors.forename: Liujiang
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Zhuo
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering Faculty, Queensland University of Technology , Garden Point Campus, Brisbane, Queensland 4001, Australia.
authors.forename: Liangzhi
authors.initials: L
authors.lastname: Kou
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ma
authors.affiliation: Bremen Center for Computational Materials Science, University of Bremen , Am Falturm 1, 28359 Bremen, Germany.
authors.forename: Bin
authors.initials: B
authors.lastname: Shao
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering Faculty, Queensland University of Technology , Garden Point Campus, Brisbane, Queensland 4001, Australia.
authors.forename: Aijun
authors.initials: A
authors.lastname: Du
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, P. R. China.|Collaborative Innovation Center of Quantum Matter, Beijing 100190, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Meng
authors.affiliation: Bremen Center for Computational Materials Science, University of Bremen , Am Falturm 1, 28359 Bremen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Frauenheim