Tailoring the Broadband Emission in All‐Inorganic Lead‐Free 0D In‐Based Halides through Sb<sup>3+</sup> Doping
Xingwen Cheng, Renfu Li, Wei Zheng, Datao Tu, Xiaoying Shang, Zhongliang Gong, Jin Xu, Siyuan Han, Xueyuan Chen
Abstract
Abstract All‐inorganic lead‐free metal halides doped with ns 2 ‐metal ions have shown great promise in optoelectronics and photovoltaics owing to their superior optical properties. Herein, a strategy is reported for tailoring the optical properties of 0D A 2 InX 5 ⋅H 2 O and A 3 InX 6 (A = Cs, Rb; X = Cl, Br) crystals via Sb 3+ doping, and the excited‐state dynamics of Sb 3+ is unveiled through temperature‐dependent photoluminescence (PL) and femtosecond transient absorption spectroscopies. Owing to the spatially confined 0D structure of the In‐based halides, Sb 3+ ions experience a strong Jahn–Taller distortion on the excited state, which results in intense PL from Sb 3+ with a broad emission band and a large Stokes shift. Through the control of A cation and the octahedral unit, tunable Sb 3+ emissions (490−750 nm) with PL quantum yields up to 91.8% are achieved in these 0D In‐based halides. These findings provide fundamental insights into the excited‐state dynamics of Sb 3+ in 0D metal halides, thus laying a foundation for future design of luminescent lead‐free 0D metal halides through ns 2 ‐metal doping towards versatile applications.