Dye-sensitized halide perovskite: A case study on calcein dye

Dye-sensitized halide perovskite systems have recently been demonstrated as promising candidates for photoelectrochemical devices. In this manuscript, we focus on the calcein dye-sensitized halide perovskite systems for aqueous-based photoelectrochemical system. This is achieved via the deposition of the commercially available self-assembled dye layer at the CH 3 NH 3 PbI 3 /TiO 2 interface. Enhanced optoelectronic properties are obtained when the calcein dye is incorporated in the perovskite-based material. The photoelectrode consisting of the calcein/CH 3 NH 3 PbI 3 hybrid film produces a photocurrent value that is orders of magnitude higher than that from a bare CH 3 NH 3 PbI 3 photoelectrode under the same condition. In addition, the calcein dye improves the light-emitting properties of the CH 3 NH 3 PbI 3 -based photoelectrode in water. The first-principles calculations suggest that multiple Lewis-acid-base coordination sites are available between the calcein dye and the halide perovskite substrate, such that the calcein dye could simultaneously enhance the light harvesting properties and passivates the perovskite electrode. This manuscript highlights the potentials of the multifunctional dye-sensitized halide perovskite materials, and facilitates the convergent understanding of halide perovskite materials for integrated optoelectronic devices.