Publication date: 23rd September 2021
Over the past decade, metal halide perovskites (MHP, CsPbX3: X = Cl, Br, I) have been widely investigated as promising materials for optoelectronics, achieving a record-breaking efficiency in solar cells. [1] From a fundamental point of view, MHP could be excellent candidates for photocatalysis due to their high photogenerated charge-carrier production and mobility as well as their narrow and tunable bandgap energy. [2] MHP with tuneable bang-gap energy could be obtained through fast substitution of bromide by iodine or chloride (CsPbBr3-yXy : X = Cl, Br, I). [3]
In this work, we investigated charge-carrier dynamics of CsPbBr3-yXy along with interfacial electron transfer from CsPbBr3-yXy to TiO2 by means of time resolved microwave conductivity (TRMC), time resolved photoluminescence (TRPL) and transient absorption spectroscopy (TAS). In order to find the optimal bandgap configuration for the most efficient charge injection, anionic ratio was varied. Charge-carrier injection from one material to another resulted in increased charge-carrier lifetime, which could positively affect the photocatalytic activity.