Search

[Display omitted] • The lattice modification of Cs 2 NaInCl 6 was conducted by Ag and Zr dopants. • The emissive color temperature was tailored from warm- to cool-white with Zr content. • Double self-trapped excitons (STEs)-based pure-white afterglow was realized, which could last over 5 h. • 40 % of Zr dopants enhanced the initial afterglow intensity for ∼ 100-fold, compared with Cs 2 Na 0.9 Ag 0.1 InCl 6. • The bands of STEs were observed in steady-state absorption spectra thanks to energy storage. The incommensurable differences between the feeding and actual doping ratios of luminescent dopants and excessive reliance on rare-earth ions become two key problems in halide perovskite-based afterglow materials, restricting the production cost and further application. Here, we prepare a series of novel lead- and rare-earth-free halide afterglow phosphors Cs 2 (Na 0.9 Ag 0.1 In) 1- x Zr x Cl 6 under an ambient condition, in which the Zr dopants modify the lattice thus tailoring the emission spectrum and trap distribution, simultaneously. The focused Cs 2 (Na 0.9 Ag 0.1 In) 0.6 Zr 0.4 Cl 6 with mainly size distribution of ∼ 0.6–1.8 μm exhibits ∼ 350–850 nm ultrabroad white luminescence under ultra-violet excitation, and the introduced traps endow the white emission with a long-persistence of over 5 h after pre-irradiation. The absorption bands of self-trapped excitons (STEs) are observed in the steady-state absorption spectra during the afterglow process, suggesting the general accepted picosecond-scaled lifetimes of STEs have been successfully prolonged to hour-scale, which provide a potential opportunity for investigating the specific behavior of STEs. [ABSTRACT FROM AUTHOR]