Low-Temperature Solution Processed Random Silver Nanowire as a Promising Replacement for Indium Tin Oxide

Area of Science:

• Materials Science
• Nanotechnology
• Renewable Energy

Background:

• Transparent conductive electrodes are crucial for solar cells.
• Indium tin oxide (ITO) is a common electrode material but requires high processing temperatures.
• Low-temperature fabrication methods are needed for cost-effective and versatile solar cell production.

Purpose of the Study:

• To demonstrate a low-temperature, solution-based process for silver nanowire (AgNW) networks.
• To evaluate AgNWs as transparent conductive top electrodes for Cu2ZnSnS4 solar cells.
• To investigate the relationship between AgNW properties and electrode performance.

Main Methods:

• Solution-based deposition of silver nanowire (AgNW) networks.
• Fabrication of Cu2ZnSnS4 solar cells with AgNW top electrodes.
• Characterization using conductive atomic force microscopy and percolation theory.
• Measurement of sheet resistance and optical transmittance.

Main Results:

• AgNW networks achieved a sheet resistance of 18 Ω/□ and ~95% transmission at 60 °C.
• AgNW electrodes outperformed indium tin oxide in Cu2ZnSnS4 solar cells.
• Optimized AgNW networks demonstrated a favorable transmittance/conductance trade-off.
• Thinner and longer nanowires were found to improve performance.

Conclusions:

• Silver nanowires provide a viable low-temperature, solution-based alternative for transparent conductive electrodes.
• This AgNW process is suitable for fabricating high-performance solar cells at low temperatures.
• The method shows promise for other low-temperature constrained solar cells like organic and perovskite types.