Field effect transistors and phototransistors based upon p-type solution-processed PbS nanowires

Area of Science:

• Materials Science
• Nanotechnology
• Solid State Physics

Background:

• Lead sulfide (PbS) nanomaterials are crucial for optoelectronic applications.
• Developing high-performance p-type PbS nanowires remains a challenge.
• Solution processing offers a scalable fabrication route.

Purpose of the Study:

• To fabricate highly crystalline p-type PbS nanowires using solution processing.
• To investigate their performance in field-effect transistors (FETs).
• To evaluate their potential for infrared photodetector applications.

Main Methods:

• Fabrication of p-type PbS nanowires via oriented attachment of nanoparticles.
• Characterization of single nanowire field-effect transistor (FET) devices.
• Analysis of photo-conductive properties under near-infrared light excitation.

Main Results:

• Achieved hole mobilities > 30 cm² V⁻¹ s⁻¹, an order of magnitude higher than previous reports for p-type PbS nanowires.
• Demonstrated gate-dependent photo-conductivities, allowing tunable device performance.
• Exhibited high responsivity (> 10⁴ A W⁻¹) and detectivity (10¹³ Jones) due to photogating effects and high crystallinity.
• Observed short switching times of 15 ms at positive gate voltages.

Conclusions:

• Solution-processed, highly crystalline p-type PbS nanowires are promising for infrared photodetectors.
• These nanowires also show potential as high-performance p-type nanowire FETs.
• The findings pave the way for advanced nanomaterial-based optoelectronic devices.