This document summarizes research on colloidal CIGS and CZTS nanocrystals for printed photovoltaics. Spray deposition techniques like airbrushing and robotic spraying allow precise control of film thickness and deposition of nanocrystal inks onto flexible plastic substrates. The document describes the synthesis of CIGS nanocrystal inks and how converting the inks to Cu(In,Ga)(S,Se)2 via high-temperature selenization can increase power conversion efficiencies to over 12%. While efficiencies of spray-deposited films are still relatively low for commercialization, the techniques allow for thin-film deposition of inorganic materials under ambient conditions and fabrication of plastic photovol

1. Colloidal CIGS and CZTS nanocrystals:
A precursor route to printed photovoltaics
Vahid A. Akhavan, Brian W. Goodfellow, Matthew G. Panthani, Chet Steinhagen, Taylor B. Harvey, C.
Jackson Stolle, Brian A. Korgel
Journal of Solid State Chemistry 189 (2012) 2–12
Sameh Hamzawy
MESC9

2. Outline
 Introduction
 Spray Deposition Technique
 Nanocrystalline Ink Synthesis
 Conclusion

3. 
•
Introduction

4. 
Spray Deposition Technique

Spray deposition by using
an Airbrush.

Spray deposition by using
Robotic Sprayer .

5. 
Why Spray Deposition Technique ?
• Precise control over film thickness
• Using of flexible, inexpensive and light-weight
plastic substrates.
• Can be readily applied to larger substrates.
• Very effective and efficient nanocrystal deposition
approach.

6. 
Nanocrystal Ink Synthesis
• The synthesis reaction equation of CIGS :
• ƞ ≈ 3.1 % on glass
substrates (2012)
• ƞ ≈ 2 % on plastic
substrates
• ƞ > 12 % has been
achieved by converting
Cu(In,Ga)Se2 NC to
Cu(In,Ga)(S,Se)2 via
selenization at 500 C.
Guo Q, Ford GM, Agrawal R, Hillhouse HW, Prog Photovolt Res Appl 2012

8. 
Conclusion
 Relatively low efficient PVs for commercialization.
 High temperature selenization lead to higher efficiency.
 Thin films deposition
of inorganic materials under
ambient conditions.
 Plastic PVs can be fabricated.

9. Thank you
for your attention