All-inorganic tin-doped Cs2BiAgCl6 double perovskites with stable blue photoluminescence for WLEDs. Issue 28 (28th June 2021)

• Record Type: Journal Article
• Authors: Huang, Dayu; Xiao, Hui; Liu, Dongjie; Ouyang, Qiuyun; Kong, Youchao; Wang, Bo; Lian, Hongzhou; Lin, Jun
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 28(2021)
• Page Start: 8862
• Page End: 8873
• Publication Date: 2021-06-28
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1tc02168k
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : A highly efficient and stable blue-emitting Cs2 BiAgCl6 :Sn 2+ with double perovskites. Abstract : Lead-free double perovskites have recently received increasing attention due to their variable band gap. In this work, tin was doped into Cs2 BiAgCl6 successfully. The doping of Sn 2+ cations can make the weak white luminescent host to produce pure blue emission peaking at around 464 nm. The internal carrier changes after Sn 2+ doping and the origin of blue emission in Cs2 BiAgCl6 :Sn 2+ was analyzed by ultrafast transient absorption (TA) techniques and time-resolved spectra. To further study the substitution feasibility of Sn 2+ –Sn 4+ for Bi 3+ –Bi 3+ pair cations, Rietveld refinement and density functional theory (DFT) calculations were performed, which proved that the crystal structures of Cs2 BiAgCl6 :Sn 2+ can exist stably. Based on these observations, we introduced blue-emitting Cs2 BiAgCl6 :Sn 2+ powder into a white LED fabricated by combining a 340 nm chip to generate stable white light with CIE coordinates of (0.31, 0.34) and a color rendering index value of 83. This work provides the methods to develop environmentally friendly blue emission from lead-free double perovskites at low cost.