Review article: tuning the gold electrode work function with thiol-based self-assembled monolayers.

Area of Science:

• Materials Science
• Surface Chemistry
• Organic Electronics

Background:

• Self-assembled monolayers (SAMs) are crucial for interfacial engineering in organic electronics.
• Work function (WF) is a key parameter influencing charge injection, transport, and device performance.
• SAMs enable precise control over surface properties like wettability, adhesion, and electrode WF.

Purpose of the Study:

• To review the modulation of gold electrode work function using thiol-derived SAMs.
• To highlight the impact of SAMs on WF for organic electronic devices.
• To provide a comprehensive overview of SAMs for gold surface modification.

Main Methods:

• Focus on WF modulation of gold electrodes.
• Utilize thiol-based SAMs for surface modification.
• Employ techniques like Kelvin Probe Force Microscopy (KPFM), Kelvin Probe (KP), and Ultraviolet Photoelectron Spectroscopy (UPS) for WF measurement.

Main Results:

• Strategic molecular design, dipole orientation, and surface coverage allow precise WF tuning.
• Key parameters influencing WF include molecular dipole, packing density, chain length, and terminal groups.
• Mixed SAMs offer advantages for achieving fine-tuned WF control.
• WF tuning across a broad range of 3.7 to 6.0 eV on gold surfaces is achievable.

Conclusions:

• SAMs are a versatile tool for advancing organic and molecular electronics through tailored interfacial engineering.
• Precise WF control via SAMs optimizes energy-level alignment in devices like OSCs, OLEDs, and OTFTs.
• Continued research into SAMs holds significant potential for future electronic device development.