Quantum confinement of PbSe nanocrystals embedded in a spacer ZnSe matrix for solar cell applications

• PbSe Nanocrystals embedded in a spacer ZnSe matrix were studied.
• PbSe NCs with 3–5 nm obtained by rapid thermal annealing of QW layers.
• Blue shift from absorption edge and emission was observed due to PbSe NCs.
• Full solar spectrum utilization for next generation solar cells were discussed.

The paper reports quantum confinement of PbSe nanocrystals (NCs) embedded in a ZnSe matrix by rapid thermal annealing of PbSe/ZnSe multiple quantum wells. The distribution of the PbSe NCs within the ZnSe matrix was observed by transmission electron microscopy and the average crystalline size of PbSe NCs was found to be 3–5 nm. The cumulative disorder and the absence of long range superstructure order due to quantum well intermixing were inferred from small angle X-ray scattering. The blue shifts in the absorption edge and band edge luminescence emission indicate formation of PbSe NCs. Finally, potential applications in solar cells are discussed.