2-dimensional hybrid perovskites activation with an organic luminophore for photovoltaic applications

The excellent optical and electronic properties of hybrid organic-inorganic perovskites make them suitable active materials for optoelectronics devices. Here we focus the attention on the 2D lead halide hybrid perovskites having the general formula (RNH3)2PbX4. These self-assembled layered materials are particularly interesting for light emitting devices such as LEDs and Lasers. More recently, Smith et al have shown that 2D perovskites can be used as an active material in hybrid perovskite solar cells (PSCs) . Compared to 3D lead halide hybrid perovskites (RNH3)PbX3 these materials present a higher long-term stability, which is one of the main issue that hinders PSCs development in an industrial scale. A great advantage of 2D perovskites is their better chemical flexibility and tunability with respect to 3D perovskites. Here an adequately chosen luminophore has been introduced inside a lead bromide hybrid perovskite to improve light–harvesting and brilliance. The functionalized perovskite exhibits a much higher brilliance than the standard one, while respecting the 2D perovskite structure . The increase of the brilliance is due to an increase of the light-harvesting: the energy absorbed by the luminophore is transfered to the perovskite, and to a resonance effect between the Frenkel exciton of the luminophore and the Wannier exciton of the perovskite. Functionalizing the organic part of hybrid perovskites with adequate dyes in order to increase light harvesting can be a promising path to enhance PSCs performance.