title: Monodisperse Dual-Functional Upconversion Nanoparticles Enabled Near-Infrared Organolead Halide Perovskite Solar Cells.
abstract: Extending the spectral absorption of organolead halide perovskite solar cells from visible into near-infrared (NIR) range renders the minimization of non-absorption loss of solar photons with improved energy alignment. Herein, we report on, for the first time, a viable strategy of capitalizing on judiciously synthesized monodisperse NaYF4 :Yb/Er upconversion nanoparticles (UCNPs) as the mesoporous electrode for CH3 NH3 PbI3 perovskite solar cells and more importantly confer perovskite solar cells to be operative under NIR light. Uniform NaYF4 :Yb/Er UCNPs are first crafted by employing rationally designed double hydrophilic star-like poly(acrylic acid)-block-poly(ethylene oxide) (PAA-b-PEO) diblock copolymer as nanoreactor, imparting the solubility of UCNPs and the tunability of film porosity during the manufacturing process. The subsequent incorporation of NaYF4 :Yb/Er UCNPs as the mesoporous electrode led to a high efficiency of 17.8 %, which was further increased to 18.1 % upon NIR irradiation. The in situ integration of upconversion materials as functional components of perovskite solar cells offers the expanded flexibility for engineering the device architecture and broadening the solar spectral use.
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
authors.forename: Ming
authors.initials: M
authors.lastname: He
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
authors.forename: Xinchang
authors.initials: X
authors.lastname: Pang
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Liu
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
authors.forename: Beibei
authors.initials: B
authors.lastname: Jiang
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
authors.forename: Yanjie
authors.initials: Y
authors.lastname: He
authors.affiliation: Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
authors.forename: Henry
authors.initials: H
authors.lastname: Snaith
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA. zhiqun.lin@mse.gatech.edu.
authors.forename: Zhiqun
authors.initials: Z
authors.lastname: Lin
keywords: near-infrared; photovoltaic devices; polymers; solar cells; upconversion nanoparticles