Snaith group

Abstract:

Inorganic perovskite quantum dots bear many unique properties that make them potential candidates for optoelectronic applications, including color display and lighting. However, the white emission with inorganic perovskite quantum dots has rarely been realized due to the anion-exchange reaction. Here, we proposed a one-pot preparation to fabricate inorganic perovskite quantum dot-based white light-emitting composites by introducing anthracene as a blue emission component. The as-prepared white light-emitting composite exhibited a photoluminescence quantum yield of 41.9%. By combining CsPb(Br/I)₃@anthracene composites with UV light-emitting device (LED) chips, white light-emitting devices with a color rendering index of 90 were realized with tunable color temperature from warm white to cool white. These results can promote the application of inorganic perovskite quantum dots in the field of white LEDs.

Abstract:

The rise of metal-halide perovskite solar cells has captivated the research community, promising to disrupt the current energy landscape. While a sizable percentage of the research done on this class of materials has been focused on the neat and iodide-rich perovskites, bromide-based perovskites can deliver substantially higher voltages because of their relatively wide band gaps of over 2 eV. The potential for efficient, high-voltage devices makes materials such as these incredibly attractive for multijunction photovoltaic applications. Here, we use the acetonitrile/methylamine solvent system to deposit smooth, highly crystalline films of CH3NH3PbBr3. By using choline chloride as a passivating agent for these films, we achieve photoluminescence quantum efficiencies of up to 5.5% and demonstrate charge-carrier mobilities of 17.8 cm2/(V s). Incorporating these films into photovoltaic devices, we achieve scanned power conversion efficiencies of up to 8.9%, with stabilized efficiencies of 7.6%, providing a simple route to realizing efficient, high-voltage CH3NH3PbBr3 planar-heterojunction devices.