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Updated: Jun 13, 2026
13:29
Harvesting Solar Energy by Means of Charge-Separating Nanocrystals and Their Solids
Published on: August 23, 2012
SnS/PbS nanocrystal heterojunction photovoltaics
Alexandros Stavrinadis1, Jason M Smith, Christopher A Cattley
1Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK. alexandros.stavrinadis@materials.ox.ac.uk
Nanotechnology
|April 15, 2010
Summary
Tin sulfide (SnS) nanocrystals show promise for solar cells. Integrating SnS with lead sulfide (PbS) creates a heterojunction with a type II band alignment, boosting open-circuit voltage (Voc) to 0.45 V.
Area of Science:
- Materials Science
- Nanotechnology
- Renewable Energy
Background:
- Tin sulfide (SnS) and lead sulfide (PbS) are emerging materials for photovoltaic applications.
- Nanocrystal synthesis allows for controlled material properties and device integration.
Purpose of the Study:
- To investigate the synthesis, characterization, and photovoltaic properties of SnS nanocrystals.
- To explore the performance of SnS/PbS heterojunctions in solar cell devices.
- To understand the electronic band alignment and charge transport mechanisms in SnS/PbS devices.
Main Methods:
- Controlled synthesis of SnS nanocrystals with sizes under 10 nm.
- Fabrication of SnS/PbS nanocrystalline film heterojunctions.
- Characterization of photovoltaic properties, including open-circuit voltage (Voc).
- Analysis of band alignment and charge carrier dynamics.
Main Results:
- SnS/PbS nanocrystalline films exhibit a type II band alignment.
- The photocurrent direction is dependent on layer order, not contact work functions.
- Placing the SnS layer adjacent to the indium tin oxide (ITO) cathode significantly increased Voc to 0.45 V.
- SnS layers were found to suppress electron injection currents in ITO/SnS/PbS/Al devices.
Conclusions:
- SnS nanocrystal films are suitable for multi-junction solar cells.
- SnS/PbS heterojunctions demonstrate intrinsic photovoltaic behavior.
- SnS plays a crucial role in optimizing charge transport and voltage in these solar cells.
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