APPLICATIONS OF TECHNOLOGY:
- Solar cells
- Higher efficiency than either pure PbS-based or pure PbSe-based PV devices
- Nanocrystals synthesized in one-pot method
A. Paul Alivisatos and colleagues at Berkeley Lab have developed solar cells based on highly confined nanocrystals of the ternary compound PbSxSe1-x. The crystalline, monodisperse alloyed nanocrystals are obtained using a one-pot, hot injection reaction. Photovoltaic devices made using these ternary nanoparticles are more efficient than either pure PbS- or pure PbSe-based nanocrystal devices.
Although little research has focused on ternary compositions of nanoparticles for solar cells, thin film solar cell studies indicate that such compositional tuning can yield significant improvements in performance. PbSe nanocrystal solar cells generate larger short circuit photocurrents while PbS nanocrystal devices with similar bandgap have shown a larger open circuit voltage. By creating ternary PbSxSe1-x, both carrier transport and voltage are optimized.
Nanocrystals are an excellent potential choice for photovoltaic device applications due to their high photoactivity, solution processability and low cost of production. A challenge for any nanoparticle-based solar cell, however, is taking advantage of quantum confinement effects to improve the optical absorption process without overly hindering the subsequent transport of charge electrodes. Various binary semiconductor nanoparticles, such as CdSe, CdTe, Cu2S, InP and InAs, have been explored for photovoltaic devices, but the reported efficiencies remain low, mostly limited by poor charge transport between the nanocrystals. The Berkeley Lab ternary compound nanocrystals, however, show promise for more efficient photovoltaic devices.
Attention potential SBIR/STTR Program applicants (FY2013, Phase 1 Release 1): Please do not contact researchers directly with technology questions. Go here to learn how you may interact with researchers during the FOA open period.
DEVELOPMENT STAGE: Bench-scale devices tested in laboratory.
STATUS: US Patent Application 20110277838A1. Available for licensing or collaborative research.
FOR MORE INFORMATION:
Ma, W., Luther, J.M., Zheng, H., Wu, Y., Alivisatos, A.P. “Photovoltaic Devices Employing Ternary PbSxSe1-x Nanocrystals,” Nano Letters, Vol. 9, No. 4, 1699-1703. 2009.
REFERENCE NUMBER: IB-2740