Ligand (biochemistry)

Electrical engineering

Physics

Quantum dot

Receptor

Nanotechnology

Nanocrystal

Engineering

Perovskite (structure)

Quantum yield

Chemistry

Materials science

Oleylamine

Photovoltaic system

Quantum mechanics

Chemical engineering

Optoelectronics

Biochemistry

Fluorescence

Advanced Materials

Lead-halide perovskite quantum dots (PQDs) or more broadly, nanocrystals possess advantageous features for solution-processed photovoltaic devices. The nanocrystal surface ligands play a crucial role in the transport of photogenerated carriers and ultimately affect the overall performance of PQD solar cells. Significantly improved CsPbI3 PQD synthetic yield and solar-cell performance through surface ligand management are demonstrated. The treatment of a secondary amine, di-n-propylamine (DPA), provides a mild and efficient approach to control the surface ligand density of PQDs, which has an apparently different working mechanism compared to previously reported surface treatments. Using an optimal DPA concentration, the treatment can simultaneously remove both long-chain insulating surface ligands of oleic acid and oleylamine, even for unpurified PQDs with high ligand density. As a result, the electrical coupling between PQDs is enhanced, leading to improved charge transport, reduced carrier recombination, and a high power conversion efficiency approaching 15% for CsPbI3 -PQD-based solar cells. In addition, the production yield of CsPbI3 PQDs can be increased by a factor of 8. These results highlight the importance of developing new ligand-management strategies, specifically for emerging PQDs to achieve scalable and high-performance perovskite-based optoelectronic devices.

Surface Ligand Management Aided by a Secondary Amine Enables Increased Synthesis Yield of CsPbI<sub>3</sub> Perovskite Quantum Dots and High Photovoltaic Performance

Surface Ligand Management Aided by a Secondary Amine Enables Increased Synthesis Yield of CsPbI3 Perovskite Quantum Dots and High Photovoltaic Performance

Surface Ligand Management Aided by a Secondary Amine Enables Increased Synthesis Yield of CsPbI₃ Perovskite Quantum Dots and High Photovoltaic Performance