Manganese-Doped, Lead-Free Double Perovskite Nanocrystals for Bright Orange-Red Emission

Peigeng Han; Xue Zhang; Cheng Luo; Wei Zhou; Songqiu Yang; Jianzhang Zhao; Weiqiao Deng; Keli Han

doi:10.1021/acscentsci.0c00056

Manganese-Doped, Lead-Free Double Perovskite Nanocrystals for Bright Orange-Red Emission

ACS Cent Sci. 2020 Apr 22;6(4):566-572. doi: 10.1021/acscentsci.0c00056. Epub 2020 Mar 17.

Authors

Peigeng Han^{1

2}, Xue Zhang³, Cheng Luo^{1

2}, Wei Zhou¹, Songqiu Yang¹, Jianzhang Zhao³, Weiqiao Deng^{1

4}, Keli Han^{1

4}

Affiliations

¹ State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, P. R. China.
² University of the Chinese Academy of Sciences, Beijing 100049, P. R. China.
³ State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China.
⁴ Institute of Molecular Sciences and Engineering, Shandong University, Qingdao 266237, P. R. China.

Abstract

Lead-free halide perovskite nanocrystals (NCs) have recently attracted attention due to their nontoxicity and stability as alternatives to lead-based perovskite NCs. Here, we report undoped and manganese-doped all-inorganic, lead-free double perovskite (DP) NCs: Cs₂NaIn _x Bi_1-x Cl₆ (0 < x < 1) and Cs₂NaIn _x Bi_1-x Cl₆:Mn (0 ≤ x ≤ 1) NCs. Undoped NCs exhibit blue emission. Through doping Mn²⁺ ions into Cs₂NaIn _x Bi_1-x Cl₆ NCs, we can avoid self-trapped exciton emission and realize bright orange red emission of Mn²⁺ dopants with the highest photoluminescence quantum efficiency of 44.6%. The photoluminescence (PL) is tunable from yellow emission to orange-red emission corresponding to a red shift from 583 to 614 nm with increasing In content. Interestingly, the PL emission of Mn-doped NCs shows a red shift from the bulk size to the nanoscale. The Mn-doped NCs show good stability in air. In addition, we further prove the process of dark self-trapped state-assisted Mn²⁺ emission in DP NCs by ultrafast transient absorption techniques.