Research Highlights: Ag-Doped Halide Perovskite Nanocrystals for Tunable Band Structure and Efficient Charge Transport

Heterovalent doping of halide perovskite nanocrystals (NCs), offering potential tunability in optical and electrical properties, remains a grand challenge. Here, we report for the first time a controlled doping of monovalent Ag⁺ into CsPbBr₃ NCs via a facile room temperature synthesis method. Our results suggest that Ag⁺ ions act as substitutional dopants to replace Pb²⁺ ions in the perovskite NCs, shifting the Fermi level down-towards the valence band and in turn inducing a heavy p-type character. Field effect transistors (FETs) fabricated with Ag⁺-doped CsPbBr₃ NCs exhibit three orders of magnitude enhancement in hole mobility at room temperature, compared with undoped CsPbBr₃ NCs. Low-temperature electrical studies further confirm the influence of Ag⁺-doping on the charge-carrier transport. This work demonstrates the tunability of heterovalent doping on the electrical properties of halide perovskite NCs, shedding lights on their future applications in versatile optoelectronic devices.

Manuscript by Zhou et al. was just accepted by ACS Energy Letters, 2019, 4, 534-541, DOI:10.1021/acsenergylett. 8b02478.